Virtual prototyping with 3D drawing programs provides a means of rapidly developing system concepts and analyzing them for form, fit, logistics, human factors integration, and general feasibility analysis.The resulting models can be studied, viewed from different angles, and even "entered" by multidisciplinary design teams working in an integrated product team environment. The authors were involved in two separate system configuration developments that benefited tirn an initial virtual prototyping approach. The first example presents the development of an electric gun concept for a ballistic missile defense application. The gun model was based on current technology developments and experiment results, and was constructed to answer the question "what configuration can be assembled in the near term that would be air transportable?" The second example illustrates the development of a small waste remediation facility, and was constructed to provide a configuration baseline fbr study. The process of converting each project's miscellaneous available technical data into a correct high-fidelity model is presented, and key technical insights provided by the virtual prototype are also presented.