Corporate information technology plays a crucial role in achieving operational and strategic goals. IT governance has therefore become a central issue to research and practice. While existing IT governance frameworks suggest the implementation of IT governance mechanisms, the link between IT governance and business performance has remained elusive. This study addresses the gap. What are the effects and value contributions of IT governance? Which interdependencies between IT and business processes have to be considered? Based on existing theories and a unique access to expert interviews, an explanatory model has been developed and presented. The findings contribute to theory building efforts in the Information Systems discipline and are highly relevant for practitioners.