ISACA has recently released the ITAF™: A Professional Practices Framework for IT Assurance.  As an ISACA member, you can download it from this link:  

ITAF is divided into three sections:
(a) Standards
(b) Guidelines
(c) Tools and techniques

It provides a single source through which IT audit and assurance professionals can seek guidance, research policies and procedures, obtain audit and assurance programmes, and develop effective reports.

All standards are mandatory; guidelines are strongly recommended.

You can refer to an introductory article "A Prelude to IT Assurance Framework", published at the IS Controls Journal Volume 3 2008, for more information.