Abstract: Apparatus for the control of admission to an establishment includes a suitable, coded entry card and a device for reading the card and providing entry when appropriate. The card includes a first region having machine-readable information encoded thereon prior to issue. The device contains at least one reader and an electronic control mechanism for examining the information read and for providing entry if the information read coincides with a preset comparison value. A further region is preferably included on the card with a value field to be cancelled. The device then contains a second reader to determine the validity of the value field. The second reader preferably functions by use of a light source and sensor. Thermographic material may be included on the card containing the cancellable value field and the device then contains a canceller.