diff --git a/dbtemplates/signal_handlers.py b/dbtemplates/signal_handlers.py
new file mode 100644
index 0000000..85093af
--- /dev/null
+++ b/dbtemplates/signal_handlers.py
@@ -0,0 +1,25 @@
+from django.contrib.sites.models import Site
+from django.db.models import Subquery
+from django.db.utils import IntegrityError
+
+from .models import Template
+
+
+def verify_template_name_uniqueness_across_all_selected_sites(sender, **kwargs):
+    if kwargs.get('action', None) == 'pre_add':
+        if kwargs.get('reverse'):
+            site = kwargs.get('instance', None)
+            template_ids = kwargs.get('pk_set', None)
+
+            template_names = Template.objects.filter(id__in=template_ids).values_list('name')
+            if template := site.template_set.filter(name__in=Subquery(template_names.values_list('name'))).first():
+                raise IntegrityError(
+                    f"Template with name '{template.name}' already exists for site '{site.name}'"
+                )
+        else:
+            template = kwargs.get('instance', None)
+            site_ids = kwargs.get('pk_set', None)
+            if site := Site.objects.filter(id__in=site_ids, template__name=template.name).first():
+                raise IntegrityError(
+                    f"Template with name '{template.name}' already exists for site '{site.name}'"
+                )