Service-Oriented Architecture (SOA) is no longer new. Five years ago, a few advanced thinkers were exploring the concept. Enterprises started experimenting with pilot projects. They liked the results. Interest and enthusiasm grew, and led to wider deployment. Now, most enterprises are planning to do something with SOA, and the early adopters are into their second or third phase developments. Everyone is asking, "How will SOA affect my enterprise?" But a better question for CEOs and CIOs to ask might be, "How will I change my enterprise to take advantage of SOA?"

SOA is a style of enterprise architecture that is radically different from earlier styles. This has led to some polarization among enterprise architects, with SOA devotees and traditional enterprise architects forming different communities. Indeed, David Linthicum, the well-known SOA expert and blogger, speaking at the recent Open Group conference in Austin, Texas, referred to them as "different tribes," which do not understand each other. There is truth in this comment. But the underlying reason is perhaps the difference between architects that have been through the SOA experience and those that have yet to do so, rather than any issue of architectural good practice. SOA has significant implications for the architect, which are really appreciated and understood only by doing it.