Weill & Ross identify 6 characteristic styles of IT governance. Each of these styles addresses governance issues and implements governance principles differently. The book reports on the authors academic studies of effectiveness. A lot to think about in this book. Good foundation for further CGEIT study, particularly helpful for the 'frameworks' domain. Highly recommended.

For me, 'strategy' is one of those elusive concepts that often gets used comfortably but without much clarity or precision much less meaning. This Kaplan & Norton book helps express and develop business strategy in a way that is likely to be actionable. Helpful for the strategic alignment domain.

For the governance professional, IT risk must be analyzed, communicated and managed in the overall enterprise context. IT or infosec risk management is otherwise incomprehensible to business management. The COSO ERM is the current best practice. Helpful for the risk management domain.

The Balanced Scorecard is the ITGI's preferred methodology for communicating strategy and measuring its achievement. More detail than found in CGEIT exam, but very good for the governance professional's toolkit. Recommended for alignment and performance measurement domains.

Probably one of the better books on IT business risk as it takes the problem beyond where the typical CISSP type is willing to proceed. Addresses issues of availability, access control, accuracy (more than 'integrity'), and agility (change management). Non-technical; highly recommended.