Dan Pilone is a Senior Software Architect with Blueprint Technologies, Inc. He has designed and implemented systems for Hughes, ARINC, UPS, and the Naval Research Laboratory. He also teaches project management, software design, and software engineering at The Catholic University in Washington D.C. Dan has written several books on software development, including "UML 2.0 in a Nutshell" (0-596-00795-7) and "UML 2.0 Pocket Reference" (0-596-10208-9), both O'Reilly.