diff --git a/argocd/deployment.yaml b/argocd/deployment.yaml
index 2fbc5a9..356e373 100644
--- a/argocd/deployment.yaml
+++ b/argocd/deployment.yaml
@@ -25,7 +25,7 @@ spec:
               mountPath: /data
       containers:
         - name: web
-          image: git.baumann.gr/adebaumann/vui:0.971
+          image: git.baumann.gr/adebaumann/vui:0.972
           imagePullPolicy: Always
           ports:
             - containerPort: 8000
diff --git a/dokumente/admin.py b/dokumente/admin.py
index 4a0e923..7613da5 100644
--- a/dokumente/admin.py
+++ b/dokumente/admin.py
@@ -94,9 +94,17 @@ class EinleitungInline(NestedStackedInline):
 
 class VorgabeForm(forms.ModelForm):
     referenzen = TreeNodeMultipleChoiceField(queryset=Referenz.objects.all(), required=False)
+    
     class Meta:
         model = Vorgabe
         fields = '__all__'
+    
+    def clean_thema(self):
+        """Validate that thema is provided."""
+        thema = self.cleaned_data.get('thema')
+        if not thema:
+            raise forms.ValidationError('Thema ist ein Pflichtfeld. Bitte wählen Sie ein Thema aus.')
+        return thema
 
 class VorgabeInline(SortableInlineAdminMixin, NestedStackedInline):
     model = Vorgabe
diff --git a/dokumente/models.py b/dokumente/models.py
index 38d66e2..1019a8b 100644
--- a/dokumente/models.py
+++ b/dokumente/models.py
@@ -169,6 +169,12 @@ class Vorgabe(models.Model):
         """
         from django.core.exceptions import ValidationError
 
+        # Check that thema is provided
+        if not self.thema_id:
+            raise ValidationError({
+                'thema': 'Thema ist ein Pflichtfeld. Bitte wählen Sie ein Thema aus.'
+            })
+
         # Check for conflicts with existing Vorgaben
         conflicts = self.find_conflicts()
         if conflicts:
diff --git a/dokumente/tests.py b/dokumente/tests.py
index a8fa968..3883439 100644
--- a/dokumente/tests.py
+++ b/dokumente/tests.py
@@ -761,6 +761,134 @@ class VorgabeSanityCheckTest(TestCase):
         self.assertIn("intersecting validity periods", report)
 
 
+class VorgabeThemaValidationTest(TestCase):
+    """Test cases for Vorgabe Thema validation"""
+    
+    def setUp(self):
+        """Set up test data for Thema validation tests"""
+        self.dokumententyp = Dokumententyp.objects.create(
+            name="Standard IT-Sicherheit",
+            verantwortliche_ve="SR-SUR-SEC"
+        )
+        self.dokument = Dokument.objects.create(
+            nummer="R0066",
+            dokumententyp=self.dokumententyp,
+            name="IT Security Standard",
+            aktiv=True
+        )
+        self.thema = Thema.objects.create(name="Organisation")
+    
+    def test_vorgabe_with_thema_passes_validation(self):
+        """Test that Vorgabe with a valid Thema passes clean() validation"""
+        vorgabe = Vorgabe(
+            order=1,
+            nummer=1,
+            dokument=self.dokument,
+            thema=self.thema,
+            titel="Test Vorgabe",
+            gueltigkeit_von=date.today()
+        )
+        # Should not raise any exception
+        try:
+            vorgabe.clean()
+        except Exception as e:
+            self.fail(f"clean() raised {e} unexpectedly!")
+    
+    def test_vorgabe_without_thema_fails_validation(self):
+        """Test that Vorgabe without Thema fails clean() validation"""
+        from django.core.exceptions import ValidationError
+        
+        vorgabe = Vorgabe(
+            order=1,
+            nummer=1,
+            dokument=self.dokument,
+            thema=None,  # No Thema
+            titel="Test Vorgabe",
+            gueltigkeit_von=date.today()
+        )
+        
+        with self.assertRaises(ValidationError) as context:
+            vorgabe.clean()
+        
+        # Check that the error message is about thema
+        self.assertIn('thema', context.exception.message_dict)
+        self.assertIn('Thema ist ein Pflichtfeld', str(context.exception))
+    
+    def test_vorgabe_form_with_thema_is_valid(self):
+        """Test that VorgabeForm with Thema is valid"""
+        from dokumente.admin import VorgabeForm
+        
+        form_data = {
+            'order': 1,
+            'nummer': 1,
+            'dokument': self.dokument.pk,
+            'thema': self.thema.pk,
+            'titel': 'Test Vorgabe',
+            'gueltigkeit_von': date.today(),
+        }
+        form = VorgabeForm(data=form_data)
+        self.assertTrue(form.is_valid(), f"Form errors: {form.errors}")
+    
+    def test_vorgabe_form_without_thema_is_invalid(self):
+        """Test that VorgabeForm without Thema is invalid"""
+        from dokumente.admin import VorgabeForm
+        
+        form_data = {
+            'order': 1,
+            'nummer': 1,
+            'dokument': self.dokument.pk,
+            'thema': '',  # Empty/missing Thema
+            'titel': 'Test Vorgabe',
+            'gueltigkeit_von': date.today(),
+        }
+        form = VorgabeForm(data=form_data)
+        self.assertFalse(form.is_valid())
+        self.assertIn('thema', form.errors)
+    
+    def test_vorgabe_form_thema_error_message_is_german(self):
+        """Test that VorgabeForm shows German error message for missing Thema"""
+        from dokumente.admin import VorgabeForm
+        
+        form_data = {
+            'order': 1,
+            'nummer': 1,
+            'dokument': self.dokument.pk,
+            'thema': '',  # Empty/missing Thema
+            'titel': 'Test Vorgabe',
+            'gueltigkeit_von': date.today(),
+        }
+        form = VorgabeForm(data=form_data)
+        form.is_valid()
+        
+        # Check that the error message is in German
+        thema_errors = form.errors.get('thema', [])
+        error_messages = ' '.join(thema_errors)
+        self.assertTrue(
+            'Pflichtfeld' in error_messages or 'pflichtfeld' in error_messages.lower(),
+            f"Expected German error message about Pflichtfeld, got: {thema_errors}"
+        )
+    
+    def test_vorgabe_model_clean_error_message_is_german(self):
+        """Test that Vorgabe.clean() shows German error message for missing Thema"""
+        from django.core.exceptions import ValidationError
+        
+        vorgabe = Vorgabe(
+            order=1,
+            nummer=1,
+            dokument=self.dokument,
+            thema=None,
+            titel="Test Vorgabe",
+            gueltigkeit_von=date.today()
+        )
+        
+        with self.assertRaises(ValidationError) as context:
+            vorgabe.clean()
+        
+        # Check error message is in German
+        error_str = str(context.exception)
+        self.assertIn('Thema ist ein Pflichtfeld', error_str)
+
+
 class SanityCheckManagementCommandTest(TestCase):
     """Test cases for sanity_check_vorgaben management command"""
     
diff --git a/pages/templates/base.html b/pages/templates/base.html
index d75aa3d..f910596 100644
--- a/pages/templates/base.html
+++ b/pages/templates/base.html
@@ -219,7 +219,7 @@
           </p>
         </div>
         <div class="col-sm-6 text-right">
-           <p class="text-muted">Version {{ version|default:"0.971" }}</p>
+           <p class="text-muted">Version {{ version|default:"0.972" }}</p>
          </div>
       </div>
     </div>