Acquisition policy and practice reflect the recurring theme that prototyping as part of weapon system development can reduce cost and time; allow demonstration of novel system concepts; provide a basis for competition; validate cost estimates, design, and manufacturing processes; and reduce or mitigate technical risk. This paper reviews four decades of RAND research on the uses of prototyping and identifies the conditions under which prototyping activities are most likely to provide benefits. The authors conclude that, although the available evidence is somewhat mixed overall, the historical record does suggest some of the conditions under which prototyping strategies are most likely to yield benefits in a development program. These conditions include ensuring that prototyping strategies and documentation are austere, not committing to production during the prototyping phase, making few significant design changes when moving to the final configuration, and maintaining strict funding limits.

The research described in this report was prepared for the Office of the Secretary of Defense (OSD). Th e research was conducted in the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community.

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