The invention provides an electro-therapeutic device for application on a human or animal body part, comprising electrodes (3), a measuring means connected thereto and arranged to measure a value of an electrical quantity, and a control unit (10) to process the measured values, wherein the control unit (10) further comprises pattern recognition means to determine a pattern in the measured values, for example by comparing with patterns stored in a memory unit (15). By means of the determined pattern, the device is able to know its position on the body, and to determine whether this position is suitable for a treatment, and to which electrodes a treatment signal must be supplied. The device is much easier to use since it does not require any user's knowledge about patterns, as this may be stored in the device itself.