Abstract: Implantable systems for controlling flow through body lumens comprise a control module and an actuator. The actuator is implanted at least partially over the body lumen to selectively constrict the lumen and control flow therethrough. The control module includes at least a power source for operating the actuator and a remotely operated switch for controlling the power source. Usually, the control module will have programmable circuitry for adjusting on/off time, degree of closure, and the like. The switch of the control module is remotely actuated by a magnetic or other signal. The control circuitry may be remotely programmed using a hand-held programmer.