A new expert system for automated process planning is presented in this book. This system is called an Intelligent Automated Process Planning system (IAPP). The IAPP system is considered a linkage between the CAD/CAM systems.This system is able to generate the process plans of prismatic as well as cylindrical part drawings. AutoCAD is used for part design representation and solid modeling. The AME (Advanced Modeling Extension) module in AutoCAD has been used for constructing the part designs. The AME provides the geometrical information of the part design through an ASCII file called CSIGES. The geometrical information is analyzed through the feature recognition program that is created specifically for the IAPP system (Intelligent Automated Process Planning)to extract the features from the part design. The feature recognition program of the IAPP system is able to recognize these features: slots, pockets (blind and through), inclined surfaces, holes (blind and through), threads, step shafts, hollow shafts, tubes, and keyways.