Abstract: An object of this invention is to facilitate the transfer of personal information by the cooperation between service providers. When the member registration is carried out for the cooperation system 7, the cooperation system 7 transmits an authentication request and data request to the authentication system 5 that ties up with the cooperation system 7. The authentication system 5 prompts the customer terminal 3 to input an ID and password for the authentication system 5. It performs the customer authentication processing by using information stored in the authentication information DB 51 when the ID and password are received from the customer terminal 3. Afterwards, it reads out personal information of the customer, which is stored in the personal information DB 53, and transmits data to the cooperation system 7.