A description is given of a device (1) for tracking the movement of a tool of a handling unit (2), having at least one directional radiator (5) that can be aligned with the tool and be tracked, and a signal evaluation unit (4) for determining the movement.The directional radiators (5) have actuators for aligning the directional beam (6) at adjustable angles with reference to a fixed spatial plane, and angle sensors for determining the current directional beam angle with reference to the spatial plane, the angle sensors being connected to the signal evaluation unit (4). Directional beam sensors (7) for detecting the directional beam (6) are arranged with a fixed reference to the tool and movably therewith, the directional beam sensors (7) being connected to the signal evaluation unit (4). The signal evaluation unit (4) is set up for tracking the directional beams (6) of the at least one directional radiator (5) onto an assigned, moving directional beam sensor (7), and for determining the arbitrary movement of the tool in three-dimensional space as a function of the directional beam angles.