These systems consist of proximity readers, door control units, door release mechanisms and a power supply. Proximity readers are fitted to one or both sides of a door to provide a secure means of access through the door. Access through the door is gained by presenting a valid fob or card to a reader. The fob/card is checked by the door control unit and if valid, the door release mechanism is operated. Door release mechanisms are rated to suit the security level of the door. The power supply is connected into a local mains electrical supply and will provide power to the system.

Reliability of tokens is excellent as they are usually 'passive', do not contain batteries and only energise when presented to a reader. 'Active' tokens are available to provide 'hands-free' operation (this can be of special significance to disable users).

Readers have a much higher resistance to vandalism than keypads as there are no moving parts. Readers are available that can be fitted so as to be inside or contained within the structure of the building.

Proximity access control offers a high level of security as each fob/card is unique and is allocated to one designated holder. Fobs/cards are extremely difficult to duplicate and have to be added to a system by an authorised person. Lost or unreturned fobs/cards are simply deleted from the system. Some systems can provide information and historical records on when fobs/cards have been used. This allows for the tracking of door operations/users, which is especially useful if there is a suspected security issue. This type of access control system can be seamlessly integrated into intercom systems, if required.