A secure card reader includes several security measures. Access to the reader's main circuitry is prevented by an enclosed whose walls contain embedded conductive paths. Breaking or grounding of one of these paths can be detected electronically. A similar arrangement of conductive paths prevent enlarging of a card received slot (9c). If tampering is detected using the embedded conductive paths, the reader's memory is wiped. The enclosure has apertures in its walls and is held in place by a potting material that extends into the apertures. A method is also provided to detect attempts to probe behind a keypad membrane. The contacts for the chip of a chip card are arranged so that their leads all extend away from the card insertion slot.