A method for managing portable data carriers in a system having at least one portable data carrier, an authentication server, and several service providers systems each including reading devices and a service provider unit. The reading devices may request an authentication information item of the data carrier and relay the authentication information item to the authentication server. The authentication server may authenticate the data carrier on the basis of the authentication information item and establish an application identity associated with the data carrier in the service provider system with the help of the security identity The established application identity associated with the data carrier may be transmitted from the authentication server to the reading device of the service provider system.