Erik Doernenburg is a Technology Principal at ThoughtWorks Inc where he is helping clients with the design and implementation of large-scale enterprise solutions. Building on his experience with J2EE, Microsoft .NET and other environments, Erik is continually exploring patterns of enterprise software, currently focusing on service-oriented architectures. Before joining ThoughtWorks Erik was Technical Director at Pixelpark UK, a new media company, where he integrated enterprise systems with web-based solutions and a variety of digital delivery channels. His career in enterprise software began in the early nineties on the NeXTSTEP platform and Erik has been an advocate of agile, test-driven, object-oriented development and Open Source software for many years. He holds a degree in Informatics from the University of Dortmund and has studied Computer Science and Linguistics at the University College Dublin.