Additive manufacturing (AM)—commonly referred to as “three-dimensional” or “3D” printing—is a prospective game changer with implications and opportunities that affect not just the Department of Defense (DOD) but the economy as a whole. The technology allows the “art to part” fabrication of complex objects from a computer model without part-specific tooling or human intervention.1 AM has already impacted a variety of industries and has the potential to present legal and economic issues with its strong economic and health-care benefits. Because of its remarkable ability to produce a wide variety of objects, AM also can have significant national security implications. The purpose of this paper is to provide a general introduction to these issues for nontechnical readers through a survey of the recent history and the current state of technology. Included in this paper is a brief review identifying key individuals and organizations shaping developments as well as projected trends.