A lithographic apparatus includes an illumination system to condition a radiation beam. A patterning support holds a patterning device that imparts the radiation beam with a pattern to form a patterned radiation beam. A substrate support holds a substrate. A projection system projects the patterned radiation beam onto the substrate. A positioning system positions the patterning support and the substrate support. The positioning system has a motor with a stator and a mover coupled to a support, and an associated motor control system with a controller providing an output for controlling currents applied to the motor. The motor control system determines a controller output required to compensate for a weight of mover and associated support, determines a deviation of this output from an output required to compensate the gravity force acting on the mover and associated support, and corrects the currents applied to the motor based on the deviation.