The transaction is started as in other cases, but the InitiateRecurrence and RecurrenceId fields must be used. At the first payment, the InitiateRecurrence field must be set to True, and an identifier must be given in the RecurrenceId field. If the first payment is successful, InitiateRecurrence = False and the stored RecurrenceId is to be sent for each further call, and the transaction is paid automatically from the source given at the first payment. We do not inform the shopper separately about the initialization of the recurrence, the website does that, but we check that.