There is no question that the successful implementation of Service?Oriented Architecture (SOA) relies on a careful and holistic approach to business planning. One of the most important tools in the evaluation, purchase, and ongoing use of SOA is the body of best practices that vendors, consultants, and customers have compiled. The promise of business agility, improved customer service, and competitive advantage with SOA is real. What varies most is the time, cost, and ease of SOA implementation. By learning from the experiences of those organizations that have been through the process and looking at the standard best practices of large?scale technology implementations, success can come earlier and more dramatically.