diff --git a/buffet/notification/notification_delegate.h b/buffet/notification/notification_delegate.h
index b2d7184..529e39d 100644
--- a/buffet/notification/notification_delegate.h
+++ b/buffet/notification/notification_delegate.h
@@ -19,6 +19,8 @@
   virtual void OnPermanentFailure() = 0;
   // Called when a new command is sent via the notification channel.
   virtual void OnCommandCreated(const base::DictionaryValue& command) = 0;
+  // Called when DEVICE_DELETED notification is received.
+  virtual void OnDeviceDeleted(const std::string& device_id) = 0;
 
  protected:
   virtual ~NotificationDelegate() = default;