An external physiologic or implanted device monitor/controller ("monitor") designed to be attached to the body, as for example, to the skin of the patient. The monitor is designed to detect the therapeutic outputs actually produced by the implanted medical device. Having knowledge of the operation of the implanted medical device, the monitor may then deduce, or decode, the physiologic conditions and/or devices conditions sensed by the implanted medical device. The monitor is then able to perform an action appropriate to the sensed condition and the specific implementation.