Many wheeled mobile robot (WMR) controllers are developed based on nonskidding and nonslipping assumptions; however, these assumptions are usually violated due to wheel tire deformation. As a result, the performance of these controllers is not guaranteed. This paper presents a GPS-based tracking controller for a car-like WMR in the presence of wheel skidding and slipping. The controller exploits real-time kinematic (RTK)-GPS and other aiding sensors to measure the WMR's posture, velocities, and perturbations due to wheel skidding and slipping for control compensation. The reported experimental results validate the control scheme.