SQL Server 2012 introduces user-defined server roles. These user-defined server roles are similar to fixed server roles with only difference is that they are created by SQL Server Administrator. SQL Administrators can create, delete or manage these user-defined server roles using T-SQL or SQL Server Management Studio. User-defined roles can be added as member of another user-defined or fixed server role. Like SQL Server logins, we can only also assign server-wide permissions to these user-defined server roles.
Checkout my article (ie Creating and Managing User-Defined roles in SQL Server 2012) that discusses how these user-defined roles can be used to simplyfy the administration of SQL Server.
This article is published on SSWUG.org.