Sage continued of a system of systems or a federation of systems after it has been initially engineered. The Department of Defense has not been unmindful of these needs, and the need for evolutionary and incremental lifecycles was recognized a decade ago and made a part of the DoD 498 standard, which is no longer operational due to the decision to use commercial standards whenever feasible. Acquisition reform is a major effort now, and has been for much of the past decade. In the effort to reduce acquisition response time, the rewrite of DoD 5000 series regulations [9] calls for evolutionary acquisition to be the preferred method for future defense acquisition programs. It also calls for simulation based acquisition to support this. Unfortunately, there is often considerable mystification over the meaning of the term and lifecycle development methods that should be used for application of the various evolutionary acquisition approaches. Some of this mystification is evident in use of expressions such as evolutionary development, spiral development, spiral acquisition, evolutionary spiral development and a host of other expressions where the meanings are not well accepted.