This paper describes conventional and enhanced methods for the monitoring and control of machining processes with a limitation to cutting and grinding machine tools. The differences between the various methods and the corresponding equipment, software and strategies are considered as well as the reasons for the limited success of some of the existing systems in use. Furthermore, the requirements of future monitoring and control systems are worked out. Therefore a systematic analysis of present and future sytems and their components is made. Finally, the function of machining process planning and its influence on the performance and the reliability of the process is discussed.