Purkinje cells are thought to control our movements by modulating their spiking activity, but the underlying code is not known. I will show that Purkinje cells in an eyeblink-related area of mouse cerebellar cortex learn to suppress their high spontaneous firing rate during the execution of a conditioned eyelid movement. To investigate if the transient suppression of Purkinje cell firing is causally linked to motor output, we inhibited Purkinje cells optogenetically and showed that we could evoke eyeblinks whose kinematic properties were precisely regulated according to the parameters of the optogenetic stimulation. Downstream neurons in the anterior interpositus nucleus showed substantial increases in firing rate during the optogenetic stimulation. These results demonstrate that a transient and synchronized suppression of Purkinje cell activity can generate movement directly, and may help sculpt the timing and kinematics of motor output via graded disinhibition of neurons in the deep cerebellar nuclei.