Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for providing a gestural interface in vehicle. In one aspect, movement data corresponding to a gesture of a driver of a vehicle is received from a radar receiver arranged to detect movement at the interior of the vehicle. The gesture is determined to be a particular gesture from among a first predetermined set of gestures for selecting an operating mode of a computing device. In response, a computing device is caused to enter an operating mode corresponding to the particular mode selection gesture, and a determination is made whether a subsequent movement of the driver represents a gesture from a second predetermined set of gestures that is different from the first predetermined set of gestures.