This paper focuses on process planning for LM and provides a survey of techniques developed to date. Process planning is performed to generate the tool paths and process parameters for an object that is to be built by a particular LM process. The steps required are: part orientation, support structure generation, slicing, path planning, and process parameter selection. STL files, solid models, and image and reverse engineering data are all considered as possible input to the process planning system. The techniques reviewed can be used for a variety of LM systems.