A multi-purpose FES system includes a multi-function, implantable stimulator for stimulating different sites in a patient's body. The stimulator includes a control unit and a receiving device. The stimulator further has a plurality of bundles of electric leads connected to the control unit, each lead terminating in at least one electrode to provide a plurality of discrete groups of electrodes associated with each site. Each group of electrodes is operable to stimulate its associated site in the patient's body, under the action of stimulation signals from the control unit, the control unit receiving signals from the receiving device. A transmitter is arranged externally of the patient's body for supplying signals transcutaneously to the receiving device of the stimulator. A controller is in communication with the transmitter via a communications interface unit.