Depending on the industry and application, views on additive manufacturing (AM), or "3D printing," range from something that will transform an industry to it being another overhyped technology that will only find niche applications. Most views fall somewhere in between, with the most common one being that it depends on the application and technology. Because of the ability to directly produce parts from a digital file, views often include dependence on when and where the part is needed. This introduces the crux of the matter, which is how to determine when the use of AM is feasible and desirable, which is made all the more complicated by the fact that not only is AM technology in general changing quickly, but also the merits of the each AM technology relative to the others are also changing. Finally, non-AM technologies are continually improving and are increasingly adding AM-like capability. As the opening report of a six-part series of SAE EDGE¿ Research Reports on AM, this paper discusses unsettled issues pertaining to the benefits, drawbacks, and trade-offs, as well as the decision-making processes to be followed in determining the feasibility and desirability of using AM. NOTE: SAE EDGE¿ Research Reports are intended to identify and illuminate key issues in emerging, but still unsettled, technologies of interest to the mobility industry. The goal of SAE EDGE¿ Research Reports is to stimulate discussion and work in the hope of promoting and speeding resolution of identified issues. SAE EDGE¿ Research Reports are not intended to resolve the challenges they identify or close any topic to further scrutiny.