The Defense Acquisition Guidebook

Systems engineering (SE) establishes the technical framework for delivering materiel capabilities to the warfighter. SE provides the foundation upon which everything else is built and supports program success. SE ensures the effective development and delivery of capability through the implementation of a balanced approach with respect to cost, schedule, performance and risk, using integrated, disciplined and consistent SE activities and processes regardless of when a program enters the acquisition life cycle. SE also enables the development of resilient systems that are trusted, assured and easily modified. The value of systems engineering is supported by the GAO Report 17-77, which indicates that, "Systems engineering is the primary means for determining whether and how the challenge posed by a program’s requirements can be met with available resources. It is a disciplined learning process that translates capability requirements into specific design features and thus identifies key risks to be resolved. Our prior best practices work has indicated that if detailed systems engineering is done before the start of product development, the program can resolve these risks through trade-offs and additional investments, ensuring that risks have been sufficiently retired or that they are clearly understood and adequately resourced if they are being carried forward.”