Abstract
In an effort to improve company operations and their results, more firms are applying the principles of βLeanββnot only to manufacturing but also to systems engineering processes. Too often, however, this is done with a shallow understanding of Lean and/or without a systems view, in which case Lean creates new problems and tensions and may not deliver expected results. Lean is not about just minimizing cost, cycle time, or waste. Lean is about maximizing value. In systems engineering or product development (PD), maximizing value may require doing more activities, not fewer. Since a process is a kind of system, a systems view and systems engineering principles are helpful. As the value of a system is more than the value of its individual components, the value of a process is more than the value of its individual activities. Value is driven not only by the presence of necessary (valueβadding) activities in the PD process but also by the way those activities work together to ensure that they use and produce the right work products, services, and information at the right time. This paper discusses how value is added in PD through work on activities and the production of deliverables. It integrates findings from several streams of research and provides bases upon which to build improved value models. It shows how the concept of Lean can broaden from asking βWhat wasteful activities can we stop doing?β to include insights from asking βWhat helpful activities can we start doing, and when?β Β© 2003 Wiley Periodicals, Inc. Syst Eng 6: 49β61, 2003. DOI 10.1002/sys.10034