This chapter begins by describing characteristics a process planning language should have. Then it discusses the extent to which four process planning languages have these characteristics. The first two of these are STEP standard process planning languages (all of AP 240 and part of AP 238). The third is part of ISO 14649. The fourth, called FBICS-ALPS, is a version of the ALPS language adapted for FBICS, a system that does automatic feature-based process planning. Next the chapter summarizes the machining features available in AP 238, ISO 14649, and AP 224. The way in which FBICS does feature-based process planning is presented and a system is described that translates FBICS plans into ISO 14649 plans (which are conceptually identical to AP 238 plans). Finally, the chapter is summarized, and improvements in FBICS needed to make it industrially useful are presented.