The wear and friction of TiN and (Ti, AI)N coatings were tested in combination with plasma nitrided hardened tool steel. Dry-sliding pin-on-ring tests were carried out. Wear behavior, coefficient of friction and contact temperature were checked with modern measurement line for the acquisition and processing of data. This hardware consists of PC computer, piezo transducer, sensors with high sensitivity, microprocessor's control measuring system, AD/DA transformer and multichannel platter. Following the tests, scanning electron microscopy (SEM), X-ray diffraction analyses (XRD) were used to elucidate the wear mechanisms and to delineate the effect of plasma nitrided underlayer on mechanical and tribological performance.