The kinemati caccuracy between axes is very important when an NC machine tool performs a contouring cut. This paper describes a theoretical and experimental investigation in which undesired kinematic errors were reduced by means of a mi croprocessor-based control scheme. A theoretical model representing the relationshiP between the dynamic behavior and the controller performance 1n one axis was first developed and then extended to two-axis contouring operations. Based on these elationships, either a closed-Joop proportional (P) or proportional-integral (PI) controller can be optimally designed to manlpulate the machine tool feed drive system to achieve high preci sion. Experiments were performed on anexi sting three-axis NC milling machine that verified the concepts introduced in this paper. The analytical controller design and implementatlon procedure are also detaled in this paper.