IT is an enterprise asset class
Like governance generally, IT governance is about the decision rights and accountabilities that encourage desirable behavior in the use of IT. It is a joint effort between IT and the business.
Enterprises have different business governance arrangements. So, for IT governance, one size clearly doesn't fit all. But meshing IT governance with business governance increases the difficulty of designing appropriate arrangements for decision making.
Those arrangements embrace styles and mechanisms most appropriate for the IT decision domain and the enterprise's business orientation. Indeed, they support more effective business governance.
A major challenge in designing IT governance and business governance is resolving boundaries and scope between the enterprise and its business units.
IT governance should be grounded in your enterprise's business orientation