Biographical Sketch: Doug Tidwell is a Senior Software Engineer in IBM’s Emerging Technology group. He was a speaker at the first XML conference in 1997, and he has been working with markup languages, Web services and SOA (the technologies beneath the cloud) for many years. His presentations have been featured at dozens of conferences around the world, and his JavaOne presentation on cloud computing earned him a Rock Star award in 2009. His job as a technology evangelist is to explain the standards and technologies behind Cloud Computing and to help customers integrate them into their overall business architectures and strategies. He is the author of many articles on IBM’s developerWorks site (ibm.com/developerWorks), and is the author of O’Reilly’s book on XSLT, a copy of which makes a perfect gift for any occasion. He lives in Chapel Hill, North Carolina with his wife, daughter and dog.