The aim of this work is to define computer-aided optimum operation and tool sequences that are to be used in Generative Process Planning System developed for rotational parts. The software developed for this purpose has a modular structure. Cutting tools are selected automatically using the machinability data, workpiece feature information, machine tool data, workholding method and the set-up number. An optimum tool sequence is characterised by a minimum number of tool changes and minimum tool travel time. Tool and operation sequence for minimum tool change are optimised with a developed optimisation method that is based on "Rank Order Clustering". (C) 2003 Elsevier Ltd. All rights reserved.