diff --git a/endpoints/api.py b/endpoints/api.py
index 7530f136f..ca7e09c14 100644
--- a/endpoints/api.py
+++ b/endpoints/api.py
@@ -1387,7 +1387,13 @@ def activate_build_trigger(namespace, repository, trigger_uuid):
       new_config_dict = request.get_json()
 
       try:
-        handler.activate(trigger.auth_token, new_config_dict)
+        repository = '%s/%s' % (trigger.repository.namespace,
+                                trigger.repository.name)
+        webhook_url = url_for('webhooks.build_trigger_webhook',
+                              repository=repository, trigger_uuid=trigger.uuid,
+                              _external=True)
+        handler.activate(trigger.uuid, webhook_url, trigger.auth_token,
+                         new_config_dict)
       except TriggerActivationException as e:
         abort(400, message = e.msg)
         return
diff --git a/endpoints/trigger.py b/endpoints/trigger.py
index 67f9e5624..0b6c4d07e 100644
--- a/endpoints/trigger.py
+++ b/endpoints/trigger.py
@@ -47,11 +47,12 @@ class BuildTrigger(object):
 
   def is_active(self, config):
     """
-    Returns True if the current build trigger is active. Inactive means further setup is needed.
+    Returns True if the current build trigger is active. Inactive means further
+    setup is needed.
     """
     raise NotImplementedError
 
-  def activate(self, auth_token, config):
+  def activate(self, trigger_uuid, standard_webhook_url, auth_token, config):
     """ 
     Activates the trigger for the service, with the given new configuration.
     """
@@ -90,9 +91,23 @@ class GithubBuildTrigger(BuildTrigger):
   def is_active(self, config):
     return 'build_source' in config and len(config['build_source']) > 0
 
-  def activate(self, auth_token, config):
-    # TODO: Add the callback web hook to the github repository.
-    pass
+  def activate(self, trigger_uuid, standard_webhook_url, auth_token, config):
+    new_build_source = config['build_source']
+    gh_client = self._get_client(auth_token)
+
+    try:
+      to_add_webhook = gh_client.get_repo(new_build_source)
+
+      webhook_config = {
+        'url': standard_webhook_url,
+        'content_type': 'json',
+      }
+
+      to_add_webhook.create_hook('web', webhook_config)
+
+
+    except Exception:
+      pass
 
   def list_build_sources(self, auth_token):
     gh_client = self._get_client(auth_token)
diff --git a/endpoints/webhooks.py b/endpoints/webhooks.py
index f153e633d..b7d0fc212 100644
--- a/endpoints/webhooks.py
+++ b/endpoints/webhooks.py
@@ -48,7 +48,7 @@ def stripe_webhook():
                 methods=['POST'])
 @process_auth
 @parse_repository_name
-def github_push_webhook(namespace, repository, trigger_uuid):
+def build_trigger_webhook(namespace, repository, trigger_uuid):
   logger.debug('Webhook received for %s/%s with uuid %s', namespace,
                repository, trigger_uuid)
   permission = ModifyRepositoryPermission(namespace, repository)