Powder bed fusion (PBF) of polymers is a collection of additive manufacturing processes that melt and fuse polymer in a powder bed. This article provides a complete suite of materials and processes involved in PBF of polymers. The discussion includes details of thermal and manufacturing issues, and safety, postprocessing, and finishing considerations, as well as of principal defects in PBF polymer parts and the mechanical properties of the parts produced by PBF. The article provides case studies on the applications of polymer PBF.