diff --git a/src/wce_crm/data_models.py b/src/wce_crm/data_models.py
index 05bc1f1..f4e2dce 100644
--- a/src/wce_crm/data_models.py
+++ b/src/wce_crm/data_models.py
@@ -102,13 +102,13 @@ def set_page_state(
 
 
 class WrapperModule(Protocol):
-    def _sync_state_to_GUI(self) -> None:
+    def _sync_state_to_GUI(self, *args, **kwargs) -> None:
         """build states for all child modules and use their `load_state` method
         to initialise them with the new data
         """
         ...
 
-    def _sync_GUI_to_state(self) -> None:
+    def _sync_GUI_to_state(self, *args, **kwargs) -> None:
         """call `get_state` method on all child modules and assign respective
         properties to state of parent module
         """
@@ -127,6 +127,10 @@ class WrapperModule(Protocol):
         """
         ...
 
+    def lock(self) -> None: ...
+
+    def unlock(self) -> None: ...
+
 
 class Module(WrapperModule, Protocol):
     def validate(self) -> list[str]:
@@ -199,6 +203,7 @@ class Page_NewInitRec_State(PageState[Module]):
 class Page_InitRecCompany_State(PageState[Module]):
     session: Session
     un_id: RecId | None = None
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
@@ -219,12 +224,14 @@ class AutoForm_State(PageState[Module]):
     cfg: AutoFormConfig
     rec_id: RecId | None = None
     form_data: dict[str, Any] | None = None
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
 class Page_InitRecPerson_State(PageState[Module]):
     session: Session
     pers_id: RecId | None = None
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
@@ -239,6 +246,7 @@ class Page_Consulting_State(PageState[Module]):
         default_factory=list
     )
     ist_geloescht: bool = False
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
@@ -257,12 +265,14 @@ class Page_Consulting_ConsultingSession_State(PageState[Module]):
     anmerkungen: str | None = None
     rueckmeldung: str | None = None
     ist_geloescht: bool = False
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
 class Page_Consulting_Table_State(PageState["Page_Consulting_ConsultingSession"]):
     session: Session
     row_states: list[Page_Consulting_ConsultingSession_State] = dc.field(default_factory=list)
+    locked: bool
 
 
 @dc.dataclass(slots=True, kw_only=True)
diff --git a/src/wce_crm/gui.py b/src/wce_crm/gui.py
index 1b279d9..026ae14 100644
--- a/src/wce_crm/gui.py
+++ b/src/wce_crm/gui.py
@@ -30,6 +30,7 @@ from PySide6.QtCore import (
     QDate,
     QDateTime,
     QEvent,
+    QKeyCombination,
     QLibraryInfo,
     QLocale,
     QObject,
@@ -40,7 +41,7 @@ from PySide6.QtCore import (
     Signal,
     qInstallMessageHandler,
 )
-from PySide6.QtGui import QAction, QFont
+from PySide6.QtGui import QAction, QFont, QKeySequence
 from PySide6.QtWidgets import (
     QAbstractItemView,
     QApplication,
@@ -145,7 +146,7 @@ QSS = """
 }
 
 *[styleClass="stempel"]:focus {
-    border: 1px dashed #cbd5e1;
+    border: 1px solid #cbd5e1;
 }
 
 QPushButton[styleClass="addButton"] {
@@ -161,6 +162,11 @@ QPushButton[styleClass="addButton"]:hover {
     background-color: #0098ff;
 }
 
+QPushButton[styleClass="addButton"]:disabled {
+    background-color: #cbd5e1;
+    color: #94a3b8;
+}
+
 QPushButton[styleClass="outlineAddButton"] {
     background-color: transparent;
     color: #007acc;
@@ -175,6 +181,13 @@ QPushButton[styleClass="outlineAddButton"]:hover {
     color: white;
 }
 
+QPushButton[styleClass="outlineAddButton"]:disabled {
+    /* background-color: #cbd5e1; */
+    background-color: transparent;
+    color: #94a3b8;
+    border: none;
+}
+
 QPushButton[styleClass="softAddButton"] {
     background-color: #e0f2fe;
     color: #0369a1;
@@ -206,6 +219,7 @@ DROPDOWN_DEFAULT: Final[str] = "--- Bitte wählen ---"
 DYNAMIC_LIST_KEY_PATTERN: Final[re.Pattern] = re.compile(r"-\[(\d+)\]")
 DATETIME_FMT: Final[str] = "%d.%m.%Y %H:%M:%S"
 DATE_FMT: Final[str] = "%d.%m.%Y"
+DEFAULT_READONLY_STYLECLASS: Final[str] = "stempel"
 
 
 def merge_dicts_to_lists(
@@ -254,16 +268,20 @@ def pformat_registry(widget_registry: WidgetRegistry) -> str:
 
 
 class CustomForm(Protocol):
-    def get_form_data(self) -> dict[str, Any]: ...
+    def get_form_data(self) -> dict[str, Any] | list[dict[str, Any]]: ...
 
     def set_form_data(self, data: Any) -> None: ...
 
-    def reset_form(self) -> None: ...
+    def reset(self) -> None: ...
 
-    def validate_form_data(self) -> list[str]: ...
+    def validate(self) -> list[str]: ...
+
+    def lock(self) -> None: ...
+
+    def unlock(self) -> None: ...
 
 
-class CustomWidget(QWidget):
+class CustomFormWidget(QWidget):
     def __init__(
         self,
         form_fields: Sequence[FormField],
@@ -279,9 +297,13 @@ class CustomWidget(QWidget):
 
     def set_form_data(self, data: Any) -> None: ...
 
-    def reset_form(self) -> None: ...
+    def reset(self) -> None: ...
 
-    def validate_form_data(self) -> list[str]: ...
+    def validate(self) -> list[str]: ...
+
+    def lock(self) -> None: ...
+
+    def unlock(self) -> None: ...
 
 
 def _add_widget_to_layout(
@@ -636,11 +658,11 @@ def reset_form(
                 DynamicListWidget,
                 DynamicDropdownWidgetNumeric,
                 DynamicDropdownWidgetOption,
-                CustomWidget,
+                CustomFormWidget,
             ),
         ):
             # custom widget classes manage their widgets on their own
-            widget.reset_form()
+            widget.reset()
 
         widget.setStyleSheet("")
 
@@ -781,7 +803,7 @@ def get_widget_value(
             DynamicListWidget,
             DynamicDropdownWidgetNumeric,
             DynamicDropdownWidgetOption,
-            CustomWidget,
+            CustomFormWidget,
         ),
     ):
         # this is a special data structure with some assumptions of the widget's internals
@@ -936,10 +958,10 @@ def validate_form_data(
                 DynamicListWidget,
                 DynamicDropdownWidgetNumeric,
                 DynamicDropdownWidgetOption,
-                CustomWidget,
+                CustomFormWidget,
             ),
         ):
-            errors_widget = widget.validate_form_data()
+            errors_widget = widget.validate()
             if not errors_widget:
                 continue
             errors.extend(errors_widget)
@@ -968,7 +990,9 @@ def validate_form_data(
     return errors
 
 
-def validate_child_modules(modules: Iterable[Module]) -> list[str]:
+def validate_child_modules(
+    modules: Iterable[Module],
+) -> list[str]:
     errors: list[str] = []
     for mod in modules:
         errors.extend(mod.validate())
@@ -976,7 +1000,87 @@ def validate_child_modules(modules: Iterable[Module]) -> list[str]:
     return errors
 
 
-class Grunderfassung_SuchWidget(CustomWidget):
+def lock_form(
+    widget_registry: WidgetRegistry,
+) -> None:
+    for registry_entry in widget_registry.values():  # type: ignore
+        widget = registry_entry["widget"]
+        form_field = registry_entry["form_field"]
+
+        if form_field.readonly:
+            continue
+
+        if isinstance(
+            widget,
+            (
+                QLineEdit,
+                QPlainTextEdit,
+                QDateEdit,
+                FlexibleDateInput,
+                FlexibleDateTimeInput,
+            ),
+        ):
+            widget.setReadOnly(True)
+        elif isinstance(widget, QComboBox):
+            widget.setEnabled(False)
+        elif isinstance(
+            widget,
+            (
+                DynamicListWidget,
+                DynamicDropdownWidgetNumeric,
+                DynamicDropdownWidgetOption,
+                CustomFormWidget,
+            ),
+        ):
+            widget.lock()
+
+        widget.setProperty("styleClass", "stempel")
+        widget.style().unpolish(widget)
+        widget.style().polish(widget)
+        widget.update()
+
+
+def unlock_form(
+    widget_registry: WidgetRegistry,
+) -> None:
+    for registry_entry in widget_registry.values():  # type: ignore
+        widget = registry_entry["widget"]
+        form_field = registry_entry["form_field"]
+
+        if form_field.readonly:
+            continue
+
+        if isinstance(
+            widget,
+            (
+                QLineEdit,
+                QPlainTextEdit,
+                QDateEdit,
+                FlexibleDateInput,
+                FlexibleDateTimeInput,
+            ),
+        ):
+            widget.setReadOnly(False)
+        elif isinstance(widget, QComboBox):
+            widget.setEnabled(True)
+        elif isinstance(
+            widget,
+            (
+                DynamicListWidget,
+                DynamicDropdownWidgetNumeric,
+                DynamicDropdownWidgetOption,
+                CustomFormWidget,
+            ),
+        ):
+            widget.unlock()
+
+        widget.setProperty("styleClass", "")
+        widget.style().unpolish(widget)
+        widget.style().polish(widget)
+        widget.update()
+
+
+class Grunderfassung_SuchWidget(CustomFormWidget):
     def __init__(
         self,
         form_fields: Sequence[FormField],
@@ -1065,7 +1169,7 @@ class Grunderfassung_SuchWidget(CustomWidget):
             button.clicked.connect(self.print_registry)
             main_layout.addWidget(button)
             button = QPushButton("Reset form")
-            button.clicked.connect(self.reset_form)
+            button.clicked.connect(self.reset)
             main_layout.addWidget(button)
             button = QPushButton("Get form data")
             button.clicked.connect(self.get_form_data)
@@ -1074,7 +1178,7 @@ class Grunderfassung_SuchWidget(CustomWidget):
             button.clicked.connect(self.set_form_data)
             main_layout.addWidget(button)
             button = QPushButton("Validate")
-            button.clicked.connect(self.validate_form_data)
+            button.clicked.connect(self.validate)
             main_layout.addWidget(button)
 
         self.update_company_data()
@@ -1170,13 +1274,13 @@ class Grunderfassung_SuchWidget(CustomWidget):
         self.fill_out_person(data)
 
     @override
-    def reset_form(self) -> None:
+    def reset(self) -> None:
         reset_form(self.widget_registry)
         self._clear_company_fields()
         self._clear_person_fields()
 
     @override
-    def validate_form_data(self) -> list[str]:
+    def validate(self) -> list[str]:
         errors = validate_form_data(self.widget_registry)
         return errors
 
@@ -1199,6 +1303,18 @@ class Grunderfassung_SuchWidget(CustomWidget):
 
         set_form_data(self.widget_registry, data, filter_keys=self.DATA_EXPORT_FIELDS)
 
+    @override
+    def lock(
+        self,
+    ) -> None:
+        lock_form(self.widget_registry)
+
+    @override
+    def unlock(
+        self,
+    ) -> None:
+        unlock_form(self.widget_registry)
+
 
 def enhanced_label(
     base_label: str,
@@ -1338,6 +1454,28 @@ class AutoForm(QWidget):
 
         self.main_layout.addSpacing(10)
 
+        # buttons (save and reset)
+        self.add_buttons = self.cfg.add_buttons
+        self.edit_buttons: EditButtons | None = None
+        if self.add_buttons:
+            self.edit_buttons = EditButtons(add_modify_btn=True, add_reset_btn=True)
+            modify_btn = self.edit_buttons.modify_button
+            assert modify_btn
+            self.modify_btn = modify_btn
+            reset_btn = self.edit_buttons.reset_btn
+            assert reset_btn
+            self.reset_btn = reset_btn
+            self.save_btn = self.edit_buttons.save_btn
+            self.delete_btn = self.edit_buttons.delete_btn
+
+            self.modify_btn.modify_activated.connect(self.unlock_form)
+            self.modify_btn.modify_deactivated.connect(self.lock_form)
+            self.save_btn.clicked.connect(self.save_data)
+            self.reset_btn.clicked.connect(self.reset_form)
+            self.delete_btn.clicked.connect(self._delete_data)
+
+            self.main_layout.addWidget(self.edit_buttons)
+
         self.top_level_form_layout = QFormLayout()
         self.main_layout.addLayout(self.top_level_form_layout)
         self.top_level_form_layout.setSpacing(10)
@@ -1351,23 +1489,7 @@ class AutoForm(QWidget):
             self.widget_registry,
         )
 
-        # buttons (save and reset)
-        self.add_buttons = self.cfg.add_buttons
-
         self.debug_form_data: dict[str, Any] = {}
-        if self.add_buttons:
-            self.edit_buttons = EditButtons(add_reset_btn=True)
-            reset_btn = self.edit_buttons.reset_btn
-            assert reset_btn
-            self.save_btn = self.edit_buttons.save_btn
-            self.reset_btn = reset_btn
-            self.delete_btn = self.edit_buttons.delete_btn
-
-            self.save_btn.clicked.connect(self.save_data)
-            self.reset_btn.clicked.connect(self.reset_form)
-            self.delete_btn.clicked.connect(self._delete_data)
-
-            self.main_layout.addWidget(self.edit_buttons)
 
         logger_auto_form.debug(
             "[Auto-Form] Initialised Auto Form Widget. Registry:%s",
@@ -1386,6 +1508,8 @@ class AutoForm(QWidget):
         logger_gui.debug("[Auto-Form] Set index to %s, new state: %s", index, self.STATE)
 
     def _disable_save(self) -> None:
+        assert self.save_btn is not None
+        assert self.edit_buttons is not None
         self.save_btn.setEnabled(False)
         self.save_btn.setText(self.edit_buttons.save_btn_txt_disabled)
 
@@ -1393,6 +1517,8 @@ class AutoForm(QWidget):
         self,
         timeout: int = 3000,
     ) -> None:
+        assert self.save_btn is not None
+        assert self.edit_buttons is not None
         QTimer.singleShot(timeout, lambda: self.save_btn.setEnabled(True))
         QTimer.singleShot(timeout + 1, lambda: self.save_btn.setShortcut("Ctrl+S"))
         self.save_btn.setText(self.edit_buttons.save_btn_txt_enabled)
@@ -1424,6 +1550,8 @@ class AutoForm(QWidget):
         if lookup_id is not None:
             logger_auto_form.debug("Load from DB:")
             loaded_data = self.cfg.data_get(lookup_id)
+        # TODO add path to avoid unnecessary loading (where the same ID is loaded
+        # twice in a row) -- use an internal marker (not state-related)
         else:
             logger_auto_form.debug("[Auto-Form] Loading: Lookup ID NULL. Do nothing!")
             return
@@ -1447,6 +1575,14 @@ class AutoForm(QWidget):
         self.STATE.form_data = None
         self._activate_delete()
 
+    def lock_form(self) -> None:
+        self.STATE.locked = True
+        self._sync_state_to_GUI("locking")
+
+    def unlock_form(self) -> None:
+        self.STATE.locked = False
+        self._sync_state_to_GUI("locking")
+
     def _get_form_data(self) -> dict[str, Any]:
         form_data = get_form_data(self.widget_registry)
         logger_auto_form.debug("[Auto-Form] Call get form data:")
@@ -1467,8 +1603,22 @@ class AutoForm(QWidget):
 
         set_form_data(self.widget_registry, data)
 
-    def _sync_state_to_GUI(self) -> None:
-        self._load_data(self.STATE.rec_id)
+    def _sync_state_to_GUI(
+        self,
+        section: Literal["form", "locking"] | None,
+    ) -> None:
+        if section is None or section == "form":
+            self._load_data(self.STATE.rec_id)
+
+        if section is None or section == "locking":
+            if self.STATE.locked:
+                if self.edit_buttons is not None:
+                    self.edit_buttons.set_modify_state(False)
+                lock_form(self.widget_registry)
+            else:
+                if self.edit_buttons is not None:
+                    self.edit_buttons.set_modify_state(True)
+                unlock_form(self.widget_registry)
 
     def _sync_GUI_to_state(self) -> None:
         form_data = self._get_form_data()
@@ -1484,7 +1634,7 @@ class AutoForm(QWidget):
         new_state: AutoForm_State,
     ) -> None:
         set_page_state(self.STATE, new_state)
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def get_state(self) -> AutoForm_State:
         self._sync_GUI_to_state()
@@ -1629,6 +1779,7 @@ class FlexibleDateInput(QWidget):
     def setReadOnly(
         self,
         read_only: bool,
+        style_class_readonly: str = DEFAULT_READONLY_STYLECLASS,
     ):
         self._read_only = read_only
         self.line_edit.setReadOnly(read_only)
@@ -1648,10 +1799,15 @@ class FlexibleDateInput(QWidget):
             )
             cleaned_date = current_text if pure else ""
             self.line_edit.setText(cleaned_date)
-            self.line_edit.setProperty("styleClass", "stempel")
+            self.line_edit.setProperty("styleClass", style_class_readonly)
         else:
             self.line_edit.setInputMask("99.99.9999;_")
             self.line_edit.setPlaceholderText("TT.MM.JJJJ")
+            self.line_edit.setProperty("styleClass", "")
+
+        self.line_edit.style().unpolish(self.line_edit)
+        self.line_edit.style().polish(self.line_edit)
+        self.line_edit.update()
 
     def _validate_input(
         self,
@@ -1821,6 +1977,7 @@ class FlexibleDateTimeInput(QWidget):
     def setReadOnly(
         self,
         read_only: bool,
+        style_class_readonly: str = DEFAULT_READONLY_STYLECLASS,
     ):
         self._read_only = read_only
         self.line_edit.setReadOnly(read_only)
@@ -1840,10 +1997,15 @@ class FlexibleDateTimeInput(QWidget):
             )
             cleaned_datetime = current_text if pure else ""
             self.line_edit.setText(cleaned_datetime)
-            self.line_edit.setProperty("styleClass", "stempel")
+            self.line_edit.setProperty("styleClass", style_class_readonly)
         else:
             self.line_edit.setInputMask("99.99.9999 99:99;_")
             self.line_edit.setPlaceholderText("TT.MM.JJJJ hh:mm")
+            self.line_edit.setProperty("styleClass", "")
+
+        self.line_edit.style().unpolish(self.line_edit)
+        self.line_edit.style().polish(self.line_edit)
+        self.line_edit.update()
 
     def _validate_input(
         self,
@@ -1990,9 +2152,10 @@ class DynamicListWidget(QWidget):
         self.sub_forms: list[SubForm] = []
         # button to add more sub forms
         self.add_btn = QPushButton("+ Hinzufügen")
-        self.add_btn.setStyleSheet(
-            "color: #0369a1; font-weight: bold; border: 1px dashed #0369a1; padding: 5px;"
-        )
+        self.add_btn.setProperty("styleClass", "outlineAddButton")
+        # self.add_btn.setStyleSheet(
+        #     "color: #0369a1; font-weight: bold; border: 1px dashed #0369a1; padding: 5px;"
+        # )
         self.add_btn.clicked.connect(self.add_entry)
         self.inner_layout.addWidget(self.add_btn)
 
@@ -2047,14 +2210,14 @@ class DynamicListWidget(QWidget):
             base_label=self.base_label,
         )
 
-    def reset_form(self) -> None:
+    def reset(self) -> None:
         while self.sub_forms:
             self.remove_entry(self.sub_forms[0])
 
         if self.add_empty_entry:
             self.add_entry()
 
-    def validate_form_data(self) -> list[str]:
+    def validate(self) -> list[str]:
         errors = validate_form_data(self.widget_registry)
         for form in self.sub_forms:
             errors.extend(validate_form_data(form.registry))
@@ -2086,6 +2249,14 @@ class DynamicListWidget(QWidget):
             current_sub_form = self.sub_forms[-1]
             set_form_data(current_sub_form.registry, sub_form_data)
 
+    def lock(self) -> None:
+        lock_form(self.widget_registry)
+        self.add_btn.setEnabled(False)
+
+    def unlock(self) -> None:
+        unlock_form(self.widget_registry)
+        self.add_btn.setEnabled(True)
+
 
 class DynamicDropdownWidgetNumeric(QWidget):
     """
@@ -2205,11 +2376,11 @@ class DynamicDropdownWidgetNumeric(QWidget):
             sub_forms=self.sub_forms,
         )
 
-    def reset_form(self) -> None:
+    def reset(self) -> None:
         # resets dynamic content when dropdown is set back to default value
         self.dropdown_widget.setCurrentIndex(0)
 
-    def validate_form_data(self) -> list[str]:
+    def validate(self) -> list[str]:
         errors = validate_form_data(self.widget_registry)
         for form in self.sub_forms:
             errors.extend(validate_form_data(form.registry))
@@ -2229,8 +2400,9 @@ class DynamicDropdownWidgetNumeric(QWidget):
 
     def set_form_data(
         self,
-        sub_form_data: dict[str, Any],
+        data: dict[str, Any],
     ) -> None:
+        # data is data of sub forms
         # delete all rows
         while self.sub_forms:
             self._remove_row()
@@ -2240,23 +2412,23 @@ class DynamicDropdownWidgetNumeric(QWidget):
         num_subforms: int = -1
         for key in self.full_keys:
             widget = self.widget_registry[key]["widget"]
-            value = sub_form_data[key]
+            value = data[key]
             set_widget_value(widget, value)
             if value is None:
                 num_subforms = 0
             else:
                 num_subforms = value
-            del sub_form_data[key]
+            del data[key]
 
         logger_get_data.debug(">>>>>>>>> Call set_form_data for DynamicDropdown")
-        logger_get_data.debug("Data before unmerge:%s", pformat(sub_form_data))
+        logger_get_data.debug("Data before unmerge:%s", pformat(data))
 
         assert len(self.sub_forms) == num_subforms
         if not self.sub_forms:
             return
 
         relevant_keys = self.sub_forms[-1].full_keys  # all keys of sub forms are the same
-        sub_data = {key: sub_form_data[key] for key in relevant_keys}
+        sub_data = {key: data[key] for key in relevant_keys}
         logger_get_data.debug(">>>> DynamicDropdownWidget. Sub data:\n%s", pformat(sub_data))
         if not sub_data:
             return
@@ -2265,8 +2437,18 @@ class DynamicDropdownWidgetNumeric(QWidget):
         logger_get_data.debug(">>>> DynamicDropdownWidget. Sub data:\n%s", pformat(sub_data))
         assert len(sub_data) == len(self.sub_forms)
 
-        for sub_form_data, sub_form in zip(sub_data, self.sub_forms):
-            set_form_data(sub_form.registry, sub_form_data)
+        for data, sub_form in zip(sub_data, self.sub_forms):
+            set_form_data(sub_form.registry, data)
+
+    def lock(self) -> None:
+        lock_form(self.widget_registry)
+        for sub_form in self.sub_forms:
+            lock_form(sub_form.registry)
+
+    def unlock(self) -> None:
+        unlock_form(self.widget_registry)
+        for sub_form in self.sub_forms:
+            unlock_form(sub_form.registry)
 
 
 class DynamicDropdownWidgetOption(QWidget):
@@ -2397,11 +2579,11 @@ class DynamicDropdownWidgetOption(QWidget):
 
         return whole_registry
 
-    def reset_form(self) -> None:
+    def reset(self) -> None:
         # resets dynamic content when dropdown is set back to default value
         self.dropdown_widget.setCurrentIndex(0)
 
-    def validate_form_data(self) -> list[str]:
+    def validate(self) -> list[str]:
         errors = validate_form_data(self.widget_registry)
         for form in self.sub_forms:
             errors.extend(validate_form_data(form.registry))
@@ -2456,6 +2638,16 @@ class DynamicDropdownWidgetOption(QWidget):
 
         set_form_data(whole_registry, data)
 
+    def lock(self) -> None:
+        lock_form(self.widget_registry)
+        for sub_form in self.sub_forms:
+            lock_form(sub_form.registry)
+
+    def unlock(self) -> None:
+        unlock_form(self.widget_registry)
+        for sub_form in self.sub_forms:
+            unlock_form(sub_form.registry)
+
 
 class NoScrollFilter(QObject):
     """disables scrolling in fields"""
@@ -2615,6 +2807,7 @@ class Page_NewInitRec(QWidget):
         req_state = Page_InitRecCompany_State(
             session=self.STATE.session,
             un_id=None,
+            locked=False,
         )
         logger_gui.debug("[Page -- InitRec] State to call: %s", req_state)
         self.company_requested.emit(req_state)
@@ -2623,6 +2816,7 @@ class Page_NewInitRec(QWidget):
         req_state = Page_InitRecPerson_State(
             session=self.STATE.session,
             pers_id=None,
+            locked=False,
         )
         logger_gui.debug("[Page -- InitRec] State to call: %s", req_state)
         self.person_requested.emit(req_state)
@@ -2632,6 +2826,7 @@ class Page_NewInitRec(QWidget):
             session=self.STATE.session,
             vorgang_id=None,
             beratungs_typ=ConsultingType.PAUSCHAL,
+            locked=False,
         )
         logger_gui.debug("[Page -- InitRec] State to call: %s", req_state)
         self.consulting_requested.emit(req_state)
@@ -2686,7 +2881,7 @@ CONFIG_GRUNDERFASSUNG_PERSONEN: Final[AutoFormConfig] = AutoFormConfig(
     form_fields=INITREC_PERSON,
 )
 
-CUSTOM_WIDGETS: Final[dict[str, type[CustomWidget]]] = {
+CUSTOM_WIDGETS: Final[dict[str, type[CustomFormWidget]]] = {
     "grunderfassung_unternehmen_suche": Grunderfassung_SuchWidget,
 }
 
@@ -2723,12 +2918,6 @@ class Page_InitRecCompany(QWidget):
         header_layout = QVBoxLayout(header_container)
         header_layout.setContentsMargins(0, 0, 0, 10)
 
-        comp_profile_btn = QPushButton("Unternehmensprofil")
-        comp_profile_btn.clicked.connect(self._request_company_profile)
-        comp_profile_btn.setSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed)
-        comp_profile_btn.setMinimumWidth(250)
-        # comp_profile_btn.setMaximumWidth(200)
-
         back_btn_main = QPushButton("← Zurück zur Übersicht")
         back_btn_main.clicked.connect(lambda: self.back_main_requested.emit())
         back_btn_main.setSizePolicy(QSizePolicy.Policy.Fixed, QSizePolicy.Policy.Fixed)
@@ -2743,12 +2932,19 @@ class Page_InitRecCompany(QWidget):
         title = QLabel("Grunderfassung Unternehmen")
         title.setStyleSheet("font-size: 20px; font-weight: bold;")
 
+        self.comp_profile_btn = QPushButton("Unternehmensprofil")
+        self.comp_profile_btn.clicked.connect(self._request_company_profile)
+        self.comp_profile_btn.setSizePolicy(
+            QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+        )
+        self.comp_profile_btn.setFixedHeight(50)
+
         header_layout.setSpacing(5)
-        header_layout.addWidget(comp_profile_btn)
-        header_layout.addSpacing(15)
         header_layout.addWidget(back_btn_step)
         header_layout.addWidget(back_btn_main)
         header_layout.addWidget(title)
+        header_layout.addSpacing(15)
+        header_layout.addWidget(self.comp_profile_btn)
         vert_layout.addWidget(header_container)
 
         # --- MAIN CONTENT ---
@@ -2774,10 +2970,12 @@ class Page_InitRecCompany(QWidget):
         auto_form_state = AutoForm_State(
             session=self.STATE.session,
             cfg=self.AUTO_FORM_CFG,
+            locked=False,
         )
         self.auto_form = AutoForm(auto_form_state)
         container_layout.addWidget(self.auto_form)
         self.auto_form.update_triggered.connect(lambda: self.update_main_page.emit())
+        self.auto_form.update_triggered.connect(self._enable_company_profile)
 
         container_layout.addSpacing(15)
 
@@ -2790,6 +2988,10 @@ class Page_InitRecCompany(QWidget):
             QLineEdit, search_widget.company_widgets["ma_unternehmensname"]
         )
 
+    def _enable_company_profile(self) -> None:
+        self._sync_GUI_to_state()
+        self._sync_state_to_GUI("comp_profile")
+
     def _request_company_profile(self) -> None:
         assert self.STATE.un_id is not None, (
             "requested company profile for a company which is not known (no ID)"
@@ -2804,14 +3006,25 @@ class Page_InitRecCompany(QWidget):
     def reset(self) -> None:
         self.auto_form.reset_form()
 
-    def _sync_state_to_GUI(self) -> None:
-        auto_form_state = AutoForm_State(
-            session=self.STATE.session,
-            cfg=self.AUTO_FORM_CFG,
-            rec_id=self.STATE.un_id,
-            form_data=None,
-        )
-        self.auto_form.load_state(auto_form_state)
+    def _sync_state_to_GUI(
+        self,
+        section: Literal["auto_form", "comp_profile"] | None,
+    ) -> None:
+        if section is None or section == "auto_form":
+            auto_form_state = AutoForm_State(
+                session=self.STATE.session,
+                cfg=self.AUTO_FORM_CFG,
+                rec_id=self.STATE.un_id,
+                form_data=None,
+                locked=self.STATE.locked,
+            )
+            self.auto_form.load_state(auto_form_state)
+
+        if section is None or section == "comp_profile":
+            if self.STATE.un_id is None:
+                self.comp_profile_btn.setEnabled(False)
+            else:
+                self.comp_profile_btn.setEnabled(True)
 
     def _sync_GUI_to_state(self) -> None:
         auto_form_state = self.auto_form.get_state()
@@ -2823,13 +3036,21 @@ class Page_InitRecCompany(QWidget):
     ) -> None:
         set_page_state(self.STATE, new_state)
 
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def get_state(self) -> Page_InitRecCompany_State:
         self._sync_GUI_to_state()
 
         return self.STATE
 
+    def lock(self) -> None:
+        self.auto_form.lock_form()
+        self.STATE.locked = True
+
+    def unlock(self) -> None:
+        self.auto_form.unlock_form()
+        self.STATE.locked = False
+
 
 class Page_InitRecPerson(QWidget):
     back_main_requested = Signal()  # back to main page
@@ -2901,7 +3122,11 @@ class Page_InitRecPerson(QWidget):
         # --- AUTO FORM LAYOUT ---
         container_layout.addSpacing(20)
         self.AUTO_FORM_CFG = CONFIG_GRUNDERFASSUNG_PERSONEN
-        auto_form_state = AutoForm_State(session=self.STATE.session, cfg=self.AUTO_FORM_CFG)
+        auto_form_state = AutoForm_State(
+            session=self.STATE.session,
+            cfg=self.AUTO_FORM_CFG,
+            locked=False,
+        )
         self.auto_form = AutoForm(auto_form_state)
         container_layout.addWidget(self.auto_form)
         self.auto_form.update_triggered.connect(lambda: self.update_triggered.emit())
@@ -2952,6 +3177,7 @@ class Page_InitRecPerson(QWidget):
             cfg=self.AUTO_FORM_CFG,
             rec_id=self.STATE.pers_id,
             form_data=None,
+            locked=self.STATE.locked,
         )
         self.auto_form.load_state(auto_form_state)
 
@@ -2971,6 +3197,14 @@ class Page_InitRecPerson(QWidget):
 
         return self.STATE
 
+    def lock(self) -> None:
+        self.auto_form.lock_form()
+        self.STATE.locked = True
+
+    def unlock(self) -> None:
+        self.auto_form.unlock_form()
+        self.STATE.locked = False
+
 
 class Page_CompanyProfile(QWidget):
     back_main_requested = Signal()  # back to main page
@@ -3246,6 +3480,7 @@ class Page_CompanyProfile(QWidget):
         req_state = Page_InitRecCompany_State(
             session=self.STATE.session,
             un_id=self.STATE.rec_id,
+            locked=True,
         )
         logger_gui.debug("[Page Company Profile] State to call: %s", req_state)
         self.back_requested.emit(req_state)
@@ -3262,6 +3497,7 @@ class Page_CompanyProfile(QWidget):
             vorgang_id=None,
             un_id=self.STATE.rec_id,
             beratungs_typ=cons_type,
+            locked=False,
         )
         self.consulting_requested.emit(new_state)
 
@@ -3277,6 +3513,7 @@ class Page_CompanyProfile(QWidget):
             vorgang_id=data.cons_id,
             un_id=self.STATE.rec_id,
             beratungs_typ=data.cons_type,
+            locked=True,
         )
         self.consulting_requested.emit(new_state)
 
@@ -3574,6 +3811,7 @@ class Page_Consulting(QWidget):
             session=session,
             vorgang_id=None,
             beratungs_typ=ConsultingType.PAUSCHAL,
+            locked=False,
         )
 
         # Hauptlayout der Seite
@@ -3658,6 +3896,12 @@ class Page_Consulting(QWidget):
             )
             db_index_set_button.clicked.connect(self._debug_load_database)
 
+            lock_button = QPushButton("Seite sperren")
+            lock_button.setSizePolicy(
+                QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Preferred
+            )
+            lock_button.clicked.connect(self._debug_load_database)
+
             db_index_layout.addWidget(self.db_index_field)
             db_index_layout.addWidget(db_index_set_button)
             container_layout.addLayout(db_index_layout)
@@ -3678,13 +3922,18 @@ class Page_Consulting(QWidget):
         container_layout.addWidget(self.info_banners_container)
 
         # --- BUTTONS ---
-        self.edit_buttons = EditButtons(add_reset_btn=False)
+        self.edit_buttons = EditButtons(add_modify_btn=True, add_reset_btn=False)
+        modify_btn = self.edit_buttons.modify_button
+        assert modify_btn
+        self.modify_btn = modify_btn
         # reset_btn = self.edit_buttons.reset_btn
         # assert reset_btn
         self.save_btn = self.edit_buttons.save_btn
         # self.reset_btn = reset_btn
         self.delete_btn = self.edit_buttons.delete_btn
 
+        self.modify_btn.modify_activated.connect(self.unlock)
+        self.modify_btn.modify_deactivated.connect(self.lock)
         self.save_btn.clicked.connect(self.save_data)
         # self.reset_btn.clicked.connect(self.reset_form)
         self.delete_btn.clicked.connect(self._delete_data)
@@ -3707,7 +3956,10 @@ class Page_Consulting(QWidget):
         type_layout.addWidget(self.type_individual_btn)
 
         # container_layout.addSpacing(50)
-        table_state = Page_Consulting_Table_State(session=self.STATE.session)
+        table_state = Page_Consulting_Table_State(
+            session=self.STATE.session,
+            locked=self.STATE.locked,
+        )
         self.table_sessions = Page_Consulting_Table(state=table_state)
         self.STATE.child_modules.append(self.table_sessions)
         container_layout.addWidget(self.table_sessions)
@@ -3743,7 +3995,10 @@ class Page_Consulting(QWidget):
         #         font-weight: bold;
         #     }
         # """)
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
+
+    def _lock_page(self) -> None:
+        pass
 
     def _delete_data(self) -> None:
         logger_page_consulting.debug("[Consulting Page] Call data delete...")
@@ -3782,7 +4037,7 @@ class Page_Consulting(QWidget):
 
         logger_page_consulting.debug("[Consulting Page] Selected cons_type: %s", cons_type)
         self.STATE.beratungs_typ = cons_type
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI("cons_type")
 
     def _debug_get_state(self) -> None:
         logger_page_consulting.debug("[Consulting Page] Call get state on table...")
@@ -3839,57 +4094,72 @@ class Page_Consulting(QWidget):
         self.info_banners.append(banner)
         self.info_banners_layout.addWidget(banner)
 
-    def _sync_state_to_GUI(self) -> None:
-        match self.STATE.beratungs_typ:
-            case ConsultingType.PAUSCHAL:
-                self.type_pauschal_btn.setChecked(True)
-            case ConsultingType.INDIVIDUAL:
-                self.type_individual_btn.setChecked(True)
+    def _sync_state_to_GUI(
+        self,
+        section: Literal["cons_type", "banners", "table", "locking"] | None,
+    ) -> None:
+        if section is None or section == "cons_type" or section == "locking":
+            match self.STATE.beratungs_typ:
+                case ConsultingType.PAUSCHAL:
+                    self.type_pauschal_btn.setChecked(True)
+                case ConsultingType.INDIVIDUAL:
+                    self.type_individual_btn.setChecked(True)
 
-        # deactivate if at least one ID is set (type is pre-defined by how
-        # the site is called)
-        if self.STATE.un_id or self.STATE.pers_id:
-            self.type_pauschal_btn.setEnabled(False)
-            self.type_individual_btn.setEnabled(False)
-        else:
-            self.type_pauschal_btn.setEnabled(True)
-            self.type_individual_btn.setEnabled(True)
+            # deactivate if at least one ID is set (type is pre-defined by how
+            # the site is called)
+            if self.STATE.un_id or self.STATE.pers_id or self.STATE.locked:
+                self.type_pauschal_btn.setEnabled(False)
+                self.type_individual_btn.setEnabled(False)
+            else:
+                self.type_pauschal_btn.setEnabled(True)
+                self.type_individual_btn.setEnabled(True)
 
         # info banners needed
-        self._clear_info_banners()
-        if self.STATE.vorgang_id is None:
-            self._add_linking_banner(
-                text="⚠️ Dieser Eintrag ist noch nicht gespeichert.",
-                button_text="",
-            )
-        else:
-            if self.STATE.un_id is None and self.STATE.pers_id is None:
+        if section is None or section == "banners":
+            self._clear_info_banners()
+            if self.STATE.vorgang_id is None:
                 self._add_linking_banner(
-                    text="⚠️ Dieser Eintrag ist noch nicht mit einer Entität verknüpft.",
-                    button_text="Jetzt verknüpfen",
-                    button_func=self._open_linking_dialogue,
-                )
-            elif (
-                self.STATE.beratungs_typ is ConsultingType.INDIVIDUAL
-                and self.STATE.pers_id is None
-            ):
-                self._add_linking_banner(
-                    text=(
-                        "⚠️ Dies ist eine Individualberatung, aber die Verknüpfgung zu "
-                        "einer Person fehlt."
-                    ),
-                    button_text="Jetzt verknüpfen",
-                    button_func=self._open_linking_dialogue,
+                    text="⚠️ Dieser Eintrag ist noch nicht gespeichert.",
+                    button_text="",
                 )
+            else:
+                if self.STATE.un_id is None and self.STATE.pers_id is None:
+                    self._add_linking_banner(
+                        text="⚠️ Dieser Eintrag ist noch nicht mit einer Entität verknüpft.",
+                        button_text="Jetzt verknüpfen",
+                        button_func=self._open_linking_dialogue,
+                    )
+                elif (
+                    self.STATE.beratungs_typ is ConsultingType.INDIVIDUAL
+                    and self.STATE.pers_id is None
+                ):
+                    self._add_linking_banner(
+                        text=(
+                            "⚠️ Dies ist eine Individualberatung, aber die Verknüpfgung zu "
+                            "einer Person fehlt."
+                        ),
+                        button_text="Jetzt verknüpfen",
+                        button_func=self._open_linking_dialogue,
+                    )
 
         # child modules
         # call to child modules' syncing method not needed because these are initialised by
         # their own "load_state" method which again calls the modules sync method
-        table_state = Page_Consulting_Table_State(
-            session=self.STATE.session,
-            row_states=self.STATE.cons_sessions,
-        )
-        self.table_sessions.load_state(table_state)
+        if section is None or section == "table":
+            table_state = Page_Consulting_Table_State(
+                session=self.STATE.session,
+                row_states=self.STATE.cons_sessions,
+                locked=self.STATE.locked,
+            )
+            self.table_sessions.load_state(table_state)
+
+        if section is None or section == "locking":
+            if self.STATE.locked:
+                self.table_sessions.lock()
+                self.edit_buttons.set_modify_state(False)
+            else:
+                self.table_sessions.unlock()
+                self.edit_buttons.set_modify_state(True)
 
     def _sync_GUI_to_state(self) -> None:
         # call to child modules' syncing method not needed because their syncing method is
@@ -3912,7 +4182,7 @@ class Page_Consulting(QWidget):
         logger_page_consulting.debug("[Consulting] Loading with request:\n%s", new_state)
         set_page_state(self.STATE, new_state)
 
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def load_database(
         self,
@@ -3960,6 +4230,7 @@ class Page_Consulting(QWidget):
         self.STATE.pers_id = data.pers_id
         self.STATE.titel = data.titel
         self.STATE.ist_geloescht = data.geloescht is not None
+        self.STATE.locked = True
 
         if update_only:
             relevant_gui_states = [s for s in self.STATE.cons_sessions if not s.ist_geloescht]
@@ -3987,10 +4258,11 @@ class Page_Consulting(QWidget):
                     thema_crm_matrix=pydantic_state.thema_crm_matrix,
                     anmerkungen=pydantic_state.anmerkungen,
                     rueckmeldung=pydantic_state.rueckmeldung,
+                    locked=self.STATE.locked,
                 )
                 self.STATE.cons_sessions.append(cons_session_state)
 
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def get_state(self) -> Page_Consulting_State:
         self._sync_GUI_to_state()
@@ -4121,6 +4393,14 @@ class Page_Consulting(QWidget):
             # always re-enable save, even if error occurred
             self._enable_save()
 
+    def lock(self) -> None:
+        self.STATE.locked = True
+        self._sync_state_to_GUI("locking")
+
+    def unlock(self) -> None:
+        self.STATE.locked = False
+        self._sync_state_to_GUI("locking")
+
 
 class Page_Consulting_ConsultingSession(QWidget):
     """child of 'Page_Consulting_DynamicTable'"""
@@ -4265,7 +4545,7 @@ class Page_Consulting_ConsultingSession(QWidget):
             layout.setStretch(i, stretch)
 
         self.setSizePolicy(QSizePolicy.Policy.Preferred, QSizePolicy.Policy.Fixed)
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def _delete_request(self) -> None:
         confirm = get_user_confirmation(
@@ -4277,18 +4557,32 @@ class Page_Consulting_ConsultingSession(QWidget):
             self.STATE.ist_geloescht = True
             self.delete_request.emit(self)
 
-    def _sync_state_to_GUI(self) -> None:
+    def _sync_state_to_GUI(
+        self,
+        section: Literal["values", "locking"] | None,
+    ) -> None:
         logger_page_consulting.debug(
             "[Page Consulting -- Consulting Session]: State = %s", self.STATE
         )
-        set_widget_value(self.user_field, self.STATE.nutzer_name)
-        if self.STATE.zeitstempel is not None:
-            set_widget_value(self.timestamp, self.STATE.zeitstempel.astimezone(TIMEZONE_CEST))
-        set_widget_value(self.contact, self.STATE.ansprechpartner)
-        set_widget_value(self.contact_type, self.STATE.kommunikationsweg)
-        set_widget_value(self.crm_link, self.STATE.thema_crm_matrix)
-        set_widget_value(self.plain_text, self.STATE.anmerkungen)
-        set_widget_value(self.response, self.STATE.rueckmeldung)
+        if section is None or section == "values":
+            set_widget_value(self.user_field, self.STATE.nutzer_name)
+            if self.STATE.zeitstempel is not None:
+                set_widget_value(
+                    self.timestamp, self.STATE.zeitstempel.astimezone(TIMEZONE_CEST)
+                )
+            set_widget_value(self.contact, self.STATE.ansprechpartner)
+            set_widget_value(self.contact_type, self.STATE.kommunikationsweg)
+            set_widget_value(self.crm_link, self.STATE.thema_crm_matrix)
+            set_widget_value(self.plain_text, self.STATE.anmerkungen)
+            set_widget_value(self.response, self.STATE.rueckmeldung)
+
+        if section is None or section == "locking":
+            if self.STATE.locked:
+                lock_form(self.widget_registry)
+                self.btn_delete.setEnabled(False)
+            else:
+                unlock_form(self.widget_registry)
+                self.btn_delete.setEnabled(False)
 
     def _sync_GUI_to_state(self) -> None:
         self.STATE.zeitstempel = self.timestamp.get_pydatetime()
@@ -4320,7 +4614,15 @@ class Page_Consulting_ConsultingSession(QWidget):
         new_state: Page_Consulting_ConsultingSession_State,
     ) -> None:
         set_page_state(self.STATE, new_state)
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
+
+    def lock(self) -> None:
+        self.STATE.locked = True
+        self._sync_state_to_GUI("locking")
+
+    def unlock(self) -> None:
+        self.STATE.locked = False
+        self._sync_state_to_GUI("locking")
 
 
 class Page_Consulting_Table(QWidget):
@@ -4481,11 +4783,11 @@ class Page_Consulting_Table(QWidget):
                 beratung_id=None,
                 nutzer_id=self.STATE.session.user_id,
                 nutzer_name=self.STATE.session.user_name,
+                locked=False,
             )
 
         row = Page_Consulting_ConsultingSession(state=row_state)
         row.delete_request.connect(self.remove_row)
-        # sys.exit(0)
 
         index = self.container_layout.count() - 1
         self.container_layout.insertWidget(index, row)
@@ -4507,15 +4809,29 @@ class Page_Consulting_Table(QWidget):
         while self.STATE.child_modules:
             self.remove_row(self.STATE.child_modules[0])
 
-    def _sync_state_to_GUI(self) -> None:
+    def _sync_state_to_GUI(
+        self,
+        section: Literal["rows", "locking"] | None,
+    ) -> None:
         self.setUpdatesEnabled(False)
 
-        self.remove_all_rows()
-        # states_to_show = [s for s in self.STATE.row_states if not s.ist_geloescht]
-        # for row_state in states_to_show:
-        for row_state in self.STATE.row_states:
-            if not row_state.ist_geloescht:
-                self.add_row(row_state, True)
+        if section is None or section == "rows":
+            self.remove_all_rows()
+            # states_to_show = [s for s in self.STATE.row_states if not s.ist_geloescht]
+            # for row_state in states_to_show:
+            for row_state in self.STATE.row_states:
+                if not row_state.ist_geloescht:
+                    self.add_row(row_state, True)
+
+        if section is None or section == "locking":
+            if self.STATE.locked:
+                self.btn_add.setEnabled(False)
+                for m in self.STATE.child_modules:
+                    m.lock()
+            else:
+                self.btn_add.setEnabled(True)
+                for m in self.STATE.child_modules:
+                    m.unlock()
 
         self.setUpdatesEnabled(True)
 
@@ -4559,8 +4875,7 @@ class Page_Consulting_Table(QWidget):
             "[Page -- Consulting] Table: Call loading from state, %s", new_state
         )
         set_page_state(self.STATE, new_state)
-
-        self._sync_state_to_GUI()
+        self._sync_state_to_GUI(None)
 
     def validate(self) -> list[str]:
         errors: list[str] = []
@@ -4572,6 +4887,14 @@ class Page_Consulting_Table(QWidget):
     def save_data(self) -> None:
         pass
 
+    def lock(self) -> None:
+        self.STATE.locked = True
+        self._sync_state_to_GUI("locking")
+
+    def unlock(self) -> None:
+        self.STATE.locked = False
+        self._sync_state_to_GUI("locking")
+
 
 class InfoBanner(QFrame):
     btn_clicked = Signal()
@@ -4672,7 +4995,9 @@ class MainWindow(QMainWindow):
         self.new_initrec_select.consulting_requested.connect(self.show_page_consulting)
         self.stack.addWidget(self.new_initrec_select)
         # SITE: 'Grunderfassung Unternehmen'
-        initrec_company_state = Page_InitRecCompany_State(session=self.STATE.session)
+        initrec_company_state = Page_InitRecCompany_State(
+            session=self.STATE.session, locked=False
+        )
         self.initrec_company = Page_InitRecCompany(initrec_company_state)
         self.initrec_company.back_main_requested.connect(self.show_main_page)
         self.initrec_company.back_requested.connect(self.show_new_entry_select)
@@ -4680,7 +5005,9 @@ class MainWindow(QMainWindow):
         self.initrec_company.company_profile_requested.connect(self.show_page_company_profile)
         self.stack.addWidget(self.initrec_company)
         # SITE: 'Grunderfassung Person'
-        initrec_person_state = Page_InitRecPerson_State(session=self.STATE.session)
+        initrec_person_state = Page_InitRecPerson_State(
+            session=self.STATE.session, locked=False
+        )
         self.initrec_person = Page_InitRecPerson(initrec_person_state)
         self.initrec_person.back_main_requested.connect(self.show_main_page)
         self.initrec_person.back_requested.connect(self.show_new_entry_select)
@@ -4826,13 +5153,17 @@ class MainWindow(QMainWindow):
         target: QWidget
         if data.type is types.InitRecType.COMPANY:
             new_state = Page_InitRecCompany_State(
-                session=self.STATE.session, un_id=data.rec_id
+                session=self.STATE.session,
+                un_id=data.rec_id,
+                locked=True,
             )
             self.initrec_company.load_state(new_state)
             target = self.initrec_company
         elif data.type is types.InitRecType.PERSON:
             new_state = Page_InitRecPerson_State(
-                session=self.STATE.session, pers_id=data.rec_id
+                session=self.STATE.session,
+                pers_id=data.rec_id,
+                locked=True,
             )
             self.initrec_person.load_state(new_state)
             target = self.initrec_person
@@ -4926,13 +5257,6 @@ def global_exception_handler(exc_type, exc_value, exc_traceback):
             "Ein unerwarteter Fehler ist aufgetreten. Die Details wurden protokolliert.",
             error_msg,
         )
-        # msg_box.setIcon(QMessageBox.Icon.Critical)
-        # msg_box.setWindowTitle("Kritischer Fehler")
-        # msg_box.setText(
-        #     "Ein unerwarteter Fehler ist aufgetreten. Die Details wurden protokolliert."
-        # )
-        # # details for user or screenshots
-        # msg_box.setDetailedText(error_msg)
         msg_box.exec()
 
     sys.exit(1)
@@ -5012,15 +5336,93 @@ def GUI_pydantic_validation_error_handling(
     msg_box.exec()
 
 
+class _ModifyButton(QPushButton):
+    modify_activated = Signal()
+    modify_deactivated = Signal()
+
+    def __init__(
+        self,
+        external_state_management: bool,
+        txt_activate: str = "Bearbeitung aktivieren (Strg + B)",
+        txt_deactivate: str = "Bearbeitung deaktivieren (Strg + B)",
+        shortcut: str = "Ctrl+B",
+        parent: QWidget | None = None,
+    ) -> None:
+        super().__init__(txt_activate, parent=parent)
+        self.txt_activate = txt_activate
+        self.txt_deactivate = txt_deactivate
+        self.custom_shortcut: (
+            QKeySequence | QKeyCombination | QKeySequence.StandardKey | str | int
+        ) = shortcut
+        self.is_modify_state = False
+        self.external_state_management = external_state_management
+
+        self.setShortcut(self.custom_shortcut)
+
+        self.clicked.connect(self._clicked)
+
+    def set_modify_state(
+        self,
+        enable_modification: bool,
+    ) -> None:
+        if enable_modification:
+            self.setText(self.txt_deactivate)
+        else:
+            self.setText(self.txt_activate)
+
+        self.setShortcut(self.custom_shortcut)
+        self.is_modify_state = enable_modification
+
+    def _clicked(self) -> None:
+        if self.is_modify_state:
+            self.setText(self.txt_activate)
+            self.modify_deactivated.emit()
+        else:
+            self.setText(self.txt_deactivate)
+            self.modify_activated.emit()
+
+        self.setShortcut(self.custom_shortcut)
+        if not self.external_state_management:
+            self.is_modify_state = not self.is_modify_state
+
+    @override
+    def setEnabled(
+        self,
+        enabled: bool,
+    ) -> None:
+        super().setEnabled(enabled)
+        if enabled:
+            self.setShortcut(self.custom_shortcut)
+
+    @override
+    def setShortcut(
+        self,
+        key: QKeySequence | QKeyCombination | QKeySequence.StandardKey | str | int,
+    ) -> None:
+        self.custom_shortcut = key
+        super().setShortcut(key)
+
+
 class EditButtons(QWidget):
     def __init__(
         self,
+        add_modify_btn: bool,
         add_reset_btn: bool,
     ) -> None:
         super().__init__()
 
         layout_btn = QHBoxLayout(self)
         layout_btn.setContentsMargins(0, 0, 0, 0)
+        # modify
+        self.modify_button: _ModifyButton | None = None
+        if add_modify_btn:
+            self.modify_button = _ModifyButton(external_state_management=True)
+            self.modify_button.setFixedHeight(50)
+            self.modify_button.setSizePolicy(
+                QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed
+            )
+            layout_btn.addWidget(self.modify_button)
+
         # save
         self.save_btn_txt_enabled = "Speichern (Strg + S)"
         self.save_btn_txt_disabled = "Wird gespeichert..."
@@ -5046,6 +5448,16 @@ class EditButtons(QWidget):
         self.delete_btn.setSizePolicy(QSizePolicy.Policy.Expanding, QSizePolicy.Policy.Fixed)
         layout_btn.addWidget(self.delete_btn)
 
+    def set_modify_state(
+        self,
+        enable_modification: bool,
+    ) -> None:
+        print(f">>>>>>>>> SET modify GROUP: {enable_modification=}")
+        if self.modify_button is not None:
+            self.modify_button.set_modify_state(enable_modification)
+        self.save_btn.setEnabled(enable_modification)
+        self.delete_btn.setEnabled(enable_modification)
+
 
 def qt_message_handler(mode, context, message):
     """forwards internal Qt C++ warnings to Python loggers"""
@@ -5067,6 +5479,9 @@ if TYPE_CHECKING:
     _m3: type[Module] = Page_Consulting_ConsultingSession
     _w1: type[WrapperModule] = Page_InitRecCompany
     _w2: type[WrapperModule] = Page_InitRecPerson
+    _f1: type[CustomForm] = DynamicListWidget
+    _f2: type[CustomForm] = DynamicDropdownWidgetNumeric
+    _f3: type[CustomForm] = DynamicDropdownWidgetOption
 
 
 def main() -> None: