diff --git a/django/contrib/admin/options.py b/django/contrib/admin/options.py
index 9eaa9e5851fc0..c0cfc2fad61e0 100644
--- a/django/contrib/admin/options.py
+++ b/django/contrib/admin/options.py
@@ -186,11 +186,11 @@ def __call__(self, request, url):
         # Delegate to the appropriate method, based on the URL.
         if url is None:
             return self.changelist_view(request)
-        elif url.endswith('add'):
+        elif url == "add":
             return self.add_view(request)
-        elif url.endswith('history'):
+        elif url.endswith('/history'):
             return self.history_view(request, unquote(url[:-8]))
-        elif url.endswith('delete'):
+        elif url.endswith('/delete'):
             return self.delete_view(request, unquote(url[:-7]))
         else:
             return self.change_view(request, unquote(url))
diff --git a/tests/regressiontests/admin_views/tests.py b/tests/regressiontests/admin_views/tests.py
index d16889f45a784..56937d8462a8d 100644
--- a/tests/regressiontests/admin_views/tests.py
+++ b/tests/regressiontests/admin_views/tests.py
@@ -458,6 +458,31 @@ def test_deleteconfirmation_link(self):
         response = self.client.get('/test_admin/admin/admin_views/modelwithstringprimarykey/%s/delete/' % quote(self.pk))
         should_contain = """<a href="../../%s/">%s</a>""" % (quote(self.pk), escape(self.pk))
         self.assertContains(response, should_contain)
+    
+    def test_url_conflicts_with_add(self):
+        "A model with a primary key that ends with add should be visible"
+        add_model = ModelWithStringPrimaryKey(id="i have something to add")
+        add_model.save()
+        response = self.client.get('/test_admin/admin/admin_views/modelwithstringprimarykey/%s/' % quote(add_model.pk))
+        should_contain = """<h1>Change model with string primary key</h1>"""
+        self.assertContains(response, should_contain)
+    
+    def test_url_conflicts_with_delete(self):
+        "A model with a primary key that ends with delete should be visible"
+        delete_model = ModelWithStringPrimaryKey(id="delete")
+        delete_model.save()
+        response = self.client.get('/test_admin/admin/admin_views/modelwithstringprimarykey/%s/' % quote(delete_model.pk))
+        should_contain = """<h1>Change model with string primary key</h1>"""
+        self.assertContains(response, should_contain)
+    
+    def test_url_conflicts_with_history(self):
+        "A model with a primary key that ends with history should be visible"
+        history_model = ModelWithStringPrimaryKey(id="history")
+        history_model.save()
+        response = self.client.get('/test_admin/admin/admin_views/modelwithstringprimarykey/%s/' % quote(history_model.pk))
+        should_contain = """<h1>Change model with string primary key</h1>"""
+        self.assertContains(response, should_contain)
+        
 
 class SecureViewTest(TestCase):
     fixtures = ['admin-views-users.xml']