Abstract: Apparatus for continuous sensing of hand and arm gestures comprises hand-held means for continuously sensing at least tempo and emphasis. These sensed parameters are represented quantitatively, and transduced by appropriate circuitry into electrical signals indicative of the parameter quantities. The signals may be used to control the performance of a musical composition (or the evolution of some other dynamic system), or may instead convey information. The signals may, for example, be provided to an interpreter that dynamically infers control commands from the gestures on a real-time basis in accordance with the generally accepted canon of musical conducting, directing the controlled system in accordance therewith. The invention may also sense one or more additional conducting parameters such as the speed and/or velocity, direction (i.e.