Renewing a subscription would seem to be a simple operation: the publisher sends a notice that a subscription is about to lapse and asks for permission to renew the subscription, or the publisher simply requests payment for a new subscription. Unfortunately, the process is not nearly as straightforward as it would appear. Many publishers or agents send a renewal notice well in advance of the end of the subscription. This is done to ensure the continued receipt of the serial. Good suppliers will send renewal notices and then allow time to respond before sending the second or third renewal notice. They will also mark the notice: 1st notice, 2nd notice, etc.