Design and manufacture of cams are complicated engineering tasks usually performed independently of each other. Therefore, a CAD/CAM system for cams would be very useful. The mathematical cam profile must be interpolated at some increment to create the numerical data for CNC machining. The interpolation method has significant effects on the dynamic performance. The focus of this paper is to develop a methodology of computer-aided design and manufacturing for precision cams by consideration of three CNC interpolation methods: linear, circular and R-Theta. Various aspects of the features of the interpolation method are explained and compared. The presented software can simulate a roughing and finishing sequence on a given cam blank. The computerised procedure is detailed with accompanying examples.