The Defense Acquisition System exists to manage the Nation's investments in technologies, programs, and product support necessary to achieve the National Security Strategy and support the United States Armed Forces. In that context, our objective is to acquire quality products that satisfy user needs with measurable improvements to mission capability at a fair and reasonable price. The fundamental principles and procedures that the Department follows in achieving those objectives are described in DoD Directive 5000.01 and DoD Instruction 5000.02 . This Defense Acquisition Guidebook is designed to complement those policy documents by providing the acquisition workforce with discretionary best practice that should be tailored to the needs of each program. Each chapter is designed to improve understanding of the acquisition process and ensure adequate knowledge of the statutory and regulatory requirements associated with the process. Discussions, explanations, and related information enable the reader to be efficient, effective, innovative, and disciplined, and to responsively provide warfighting capability. Each chapter lists potential ways the program manager or assigned manager can satisfy mandatory process requirements and meet staff expectations for other activities. Differences of view regarding discretionary practice will be resolved by the Milestone Decision Authority. Chapter 1, Department of Defense Decision Support Systems, presents an overview of the Defense Department's decision support systems for strategic planning and resource allocation, the determination of capability needs, and the acquisition of systems. Chapter 2, Program Strategies, provides information and guidance needed to develop a Technology Development Strategy and to develop and maintain a program-level Acquisition Strategy. Chapter 3, Affordability and Life-cycle Resource Estimates, addresses acquisition program affordability and resource estimation and describes the concept of program life-cycle cost and the processes for conducting Analysis of Alternatives. The chapter discusses specific milestone review procedures, expectations, and best practices for a variety of topics related to acquisition program affordability, cost, and manpower. The chapter further describes the role of both DoD Component cost estimates and independent cost estimates in support of the DoD acquisition system. Chapter 4, Systems Engineering, outlines DoD guidance on systems engineering, and explains expectations for completing the Systems Engineering Plan (SEP). The chapter describes standard systems engineering processes and how they apply to the DoD acquisition system. It addresses the systems engineering principles that a program manager should apply to achieve a balanced system solution. Chapter 5, Life-cycle Logistics, provides the associated guidance the Program Manager (PM), Product Support Manager (PSM), and Life-Cycle Logisticians can use in influencing the design and providing effective product support. Chapter 6, Human Systems Integration, addresses the human systems elements of the systems engineering process. It will help the program manager design and develop systems that effectively and affordably integrate with human capabilities and limitations; and it makes the program manager aware of the staff resources available to assist in this endeavor. Chapter 7, Acquiring Information Technology, Including National Security Systems, explains how the Department of Defense complies with statutory and regulatory requirements for acquiring Information Technology and National Security Systems and in using a network-centric strategy to transform DoD warfighting, business, and intelligence capabilities. The chapter also provides descriptions and explanations of the Clinger-Cohen Act and many other associated topics and concepts, and discusses many of the activities that enable the development of net-centric systems.