Abstract: An interactive input system comprises an interactive surface, an illumination source projecting light onto the interactive surface such that a shadow is cast onto the interactive surface when a gesture is made by an object positioned between the illumination source and the interactive surface, at least one imaging device capturing images of a three-dimensional (3D) space in front of the interactive surface, and processing structure processing captured images to detect the shadow and object therein, and determine therefrom whether the gesture was performed within or beyond a threshold distance from the interactive surface and execute a command associated with the gesture.