The system consists of four modules: a database, a cutter selection module, a cutting condition design module and a learning module. The database consists of four data files: work material data file, machine tool data file, machining plan data file (which defines desirable material removal rate, surface finish, cutting speed, feed, depth of cut, etc.) and cutter data file. The cutter selection module is developed based on fuzzy logic, in which the cutter selection is conducted in three steps. First, the input information is "'fuzzyized". Next, using the fuzzy correlation functions, cutter grades and cutters are selected. Then, the selected grades and cutters are searched against the cutter data file to check the availability. The cutting condition design module is developed based on fuzzy non-linear programming and user interactive graphics. The learning module is developed so that users can fine-tune the fuzzy functions to further improve the performance of the system. The system has two distinct features: (1) it can select cutters and design cutting conditions based on partial and imprecise information, and (2) it selects commercial cutter products used on shop floors. The use of the system is demonstrated using two examples. d f r C D L M(x) (M(x,c,.c2, )) M(y/x) MT T V W NOMENCLATURE depth of cut (mm); feed (mm/rev), which also equals the chip thickness; cutter nose radius (mm); cutter nose radius type; diameter of the workpiece (mm); length of cut (mm); fuzzy membership function of x (with parameters c~, c2, ); fuzzy membership function of y given x; machining type; cutter thickness type; cutting speed (m/min); work material type.