diff --git a/keystone/conf/policy.py b/keystone/conf/policy.py
index f5268aa16..e9dca0b86 100644
--- a/keystone/conf/policy.py
+++ b/keystone/conf/policy.py
@@ -19,8 +19,10 @@ driver = cfg.StrOpt(
     'driver',
     default='sql',
     help=utils.fmt("""
-Entrypoint for the policy backend driver in the keystone.policy namespace.
-Supplied drivers are rules and sql.
+Entry point for the policy backend driver in the `keystone.policy` namespace.
+Supplied drivers are `rules` (which does not support any CRUD operations for
+the v3 policy API) and `sql`. Typically, there is no reason to set this option
+unless you are providing a custom entry point.
 """))
 
 list_limit = cfg.IntOpt(