diff --git a/docs/api-guide/authentication.md b/docs/api-guide/authentication.md
index 7caeac1e2..1a1c68b84 100755
--- a/docs/api-guide/authentication.md
+++ b/docs/api-guide/authentication.md
@@ -265,6 +265,12 @@ This authentication class depends on the optional [django-oauth2-provider][djang
         'provider.oauth2',
     )
 
+Then add `OAuth2Authentication` to your global `DEFAULT_AUTHENTICATION` setting:
+
+    'DEFAULT_AUTHENTICATION_CLASSES': (
+        'rest_framework.authentication.OAuth2Authentication',
+    ),
+
 You must also include the following in your root `urls.py` module:
 
     url(r'^oauth2/', include('provider.oauth2.urls', namespace='oauth2')),