Several approaches are explored and developed to improve the contouring accuracy in CNC machines. A tuning procedure is proposed to tune the gains so as to achieve matched axial dynamics. The contouring accuracy for both linear and circular contours can be significantly improved. For circular contours, the radial errors resulting from the limited bandwidth of the axial dynamics can be further reduced by feedforward compensation. A two-stage stiction compensation scheme is proposed to reduce or eliminate the contour errors caused by stiction. A model-based Taylor series expansion error...