A motor vehicle hands-free device includes a communication interface designed so that at least one first mobile telephone and one second mobile telephone can be connected to the motor vehicle hands-free device, in particular in parallel or simultaneously, a control device designed so that mobile telephone address book entries from the first mobile telephone and mobile telephone address book entries from the second mobile telephone can be transferred to the motor vehicle hands-free device via the radio interface, and a common address book that can be generated on the basis of the mobile telephone address book entries of the first mobile telephone and the mobile telephone address book entries of the second mobile telephone.