Which is the fifth phase of the Defense Acquisition System?

• A. Materiel Solutions Analysis
• B. Technology Maturation and Risk Reduction (TMRR)
• C. Production and Deployment
• D. Operations and Sustainment

Answer: (D)

The Defense Acquisition System advances a program through a sequence that takes a system from idea to ongoing use. The fifth phase is Operations and Sustainment, which covers the long-term use of the system after it has been produced and deployed. In this phase, the focus shifts to keeping the system ready and effective over its life: ongoing maintenance, supply and logistics support, software updates, contractor support, and managing life-cycle costs. It also involves evaluating performance, implementing upgrades as needs evolve, and planning for disposal or divestment when the system reaches the end of its useful life. The earlier phases—identifying a problem and potential solutions, maturing technology, and developing and producing the system—lead up to this long-term support stage, making Operations and Sustainment the correct fifth phase.