Identify Permissions with sp_helprotect

sp_helprotect reports permissions on a stored procedure (or any other database object).

For example:
sp_helprotect byroyalty
grantor    grantee    type  action    object    column  grantable
---------  ---------  ----  --------- -------   -----   ---------
dbo        public     Grant Execute   byroyalty All     FALSE
 
(return status = 0)