The publication of Department of Defense (DOD) Directives 5000.1 and 5000.2 established a preference for the use of evolutionary acquisition and spiral development in the acquisition of complex weapon systems. NSS Acquisition Policy 03-01 provided some space-oriented customization and, similarly to the original DOD directives, also positioned Evolutionary Acquisition and Spiral Development as preferred strategies for the space domain. The tutorial's key objectives are to establish proper life cycle modeling foundations, and to emphasize that these approaches should be implemented not simply for policy compliance's sake, but because they represent a prudent risk mitigation strategy. Besides the Spiral Development Model, more development organizations have chosen RUP as their main development life cycle model. A secondary objective of this presentation is to explain the similarities and differences between Spiral Development and RUP, and provide tangible life cycle modeling guidelines for the acquisition organizations during the formative stages of the contracting process.