The Department of Defense (DoD) must focus on sustaining legacy weapons systems that are no longer in production, but are expected to remain a key component of our defense capability for decades to come. Despite the fact that these legacy systems are no longer in the acquisition phase, software upgrade cycles are needed to refresh their capabilities every 18 to 24 months. In addition, significant modernization can often be made by more extensive, focused software upgrades with relatively modest hardware changes. In this podcast, Mike Phillips discusses effective sustainment engineering efforts in the Army and Air Force, using examples from across its software engineering centers. These examples are tied to SEI research on capability maturity models, agility, and the Architecture Analysis and Design Language (AADL) modeling notation.