A transferer terminal accesses its account (of the transferer) to receive a list of electronic tickets contained in his account, selects a ticket which is to be transferred, transmits that electronic ticket, an account address of a transferee and a demand for transfer to the account, which in turn accesses an account of a transferee to receive an account addreess certificate, which is then verified by a terminal. A result of verification is transmitted to the account of transferer, whereby the electronic ticket is transmitted from the account of the transferer to the account the transferee. The account of the transferee verifies the received electronic ticket, and upon successful verification, it transmits such result to the account of the transferer, which then demands a certificate of transfer with signature from the transferer terminal. The transferer terminal demands a signature to be attached to the certificate of transfer from a portable processor. The certificate of transfer with signature which is thus obtained is then transmitted to the account of the transferer, which then transmits it to the account of the transferee. The account of the transferee retains the received certificate of transfer with signature together with the electronic ticket.