The Software Engineering Institute (SEI) conducted the Software Upgrade Workshop for Legacy Systems at the Redstone Arsenal June 5-7, 2001. The workshop captured experiences from software upgrade efforts for the Abrams, Bradley, Patriot, Apache Longbow, and Multiple Launch Rocket programs. Workshop participants explored strategies that worked and those that failed, and the obstacles that were encountered. They addressed pre-award planning, project management, software and systems, mandates, and deployment. Their effort resulted in a set of recommendations and guidelines to help organizations improve the process of upgrading legacy systems.