Fixturing Surface Accessibility AnalysisFixturing is an important manufacturing activity in the production cycle. The computer-aided fixture design (CAFD) technique has been developed and became part of CAD/CAM integration. CAFD consists of three major aspects: setup planning, fixture planning, and fixture configuration design. An automated modular fixture configuration design system has been devel oped and applied to industrial practice. This chapter presents a technical problem involved in the development of automated fixture planning systems-the accessibility analysis of a fixturing surface on workpiece. The fixturing surface accessibility should be correctly assessed to reflect the ex tent of ease of placing a fixture component in contact with the fixturing surface. The objective of accessibility analysis is to help the fixture planning fulfill the optimum selection of fixturing surfaces and points on workpiece. First, several basic criteria for evaluating the eligibility of a surface being a preliminary candidate fixturing surface are discussed. Second, by applying a discretization technique, an accessibility model of fixturing surfaces is established based on an overall evaluation of the accessibility of discrete points on the surface. Finally, the implementation issue and an analysis/ design example are presented.