A new, vacuum compatible piezo-driven rotation device (piezo-rotor) based on inertial sliding has been developed. The piezo-rotor has one degree of freedom, nanoradial resolution, and unlimited range. As a result of the simple configuration and the use of piezo-actuators, the piezo-rotor is extremely compact. It is well suited for specimen rotation in the vacuum chamber of a transmission electron microscope because the piezos do not create a magnetic field. Although the piezo-rotor has been designed to work in a vacuum, it can be used in many other rotation and positioning applications. To test the performance of the piezo-rotor, a simple, easy-to-manufacture setup was used, whose dimensions are larger than we wanted in our application. Nevertheless, scaling laws show that further miniaturization will not affect the working of the piezo-rotor, so it can be used as an alternative in some volume-critical applications. The tested configuration has a maximum rotation speed on the order of 1 rad/s at drive frequencies of some kHz. Torques on the order of 10−3 Nm have been measured. The positioning resolution depends on the drive electronics, the quality of the bearing surfaces, and the rotor dimensions. Theoretically, the highest angular resolution is 1 nrad. The spindle speed or torque can be optimized by studying the friction process, the application of special coatings, the variation of the wave form frequency, its amplitude, and the axial preload. The piezo-rotor has been shown to be reliable and robust.