IT Engagement Model
One of the key ingrediance for success is clearly defining the roles and responsibilities within IT. There are multiple stake holders in IT with each doing their best to provide the highest level of support to the business. Most of the time this results in people stepping over each other - especially as there generally is a not a clear definition of everyone's task. Most of the project failures are due to the confusion is the definition of the roles between the PMO, Project Manager and the Enterprise Architects, resulting in resposiblities overlap and lack of making decisions. Gartner has produced an excellent job of defining the IT engagement model at a very high-level and is independent whether organizations adopt SOA or not.