An access control system includes at least one door fitting to a secured area of a building and at least one identification code on a mobile data carrier. The identification code is read by a read device of a door fitting. If the read-in identification code is valid, access is granted to the area secured by the door fitting. An authorization code is transmitted from a processor via at least one communication connection to a central processor. A verification step is carried out to determine whether the transmitted authorization code corresponds to a valid authorization code for an area profile. Upon successful verification of the transmitted authorization code, write and read rights for the area profile are released to the processor transmitting the authorization code. The released area profile is changed by the processor via a communication connection.