If you are involved in defining Enterprise Architectural Solutions for large organisation, publicly owned or government bodies then I would recommend reading this book.
I have for, many years, made use of Architectural process frameworks such as TOGAF and IAF in shaping the high level approach to defining an enterprise architecture and although this book is not aimed specifically at these it does provides a large number of considerations that I believe should appear in high level architecture definition.
Understanding of the organisational model, the maturity of the IT and how it aligns with the business model (as-is and to-be), is key to both determining and justifying technical solutions. This thinking would be beneficial to be factored into considerations made in the TOGAF 9 Preliminary and Architecture Vision phases of architecture definition which define the Contextual characteristics of the Enterprise Architecture.
The book includes good examples in the areas of Organisation Models, Architecture Maturity, Business and IT Engagement as well as providing an architecture maturity migration path.
If you are interested in SOA and ESB then this also provides hooks to link your thinking into as it also includes the perspectives of shared services, data integration and standardisation in the definitions of operating models and architecture maturity.
hope that helps.