An improved external charger for an implantable medical device is disclosed in which charging is at least partially controlled based on a determined position of the external charger, which position may be indicative of the pressure between the external charger and a patient's tissue. The improved external charger includes one or more position determination elements, e.g., an accelerometer or gyrometer, and control circuitry for controlling the external device in accordance with the determined position. The determined position of the external charger can be used to control charging, for example, by suspending charging, by adjusting the intensity of charging, by adjusting a maximum set point temperature for the external charger, or issuing an alert via a suitable user interface. By so controlling the external charger on the basis of the determined position, the external charger is less likely to create potentially problematic or uncomfortable conditions for the user.
