Responsible Handling of Billing Information?

moving on asks: "I've been asked by a client to build a fee based subscription service using surepay as the vendor for processing credit card transactions. Subscribers to the service will be billed X amount per month and that is the rub. Surepay does not offer recurring billing so I will need to store credit card numbers and related info. The question is then, how does one best do this in the most responsible manner?" The trick here is giving consumers the service they have come to expect from most websites, without exposing their personal information to would-be thieves. Do you think such a system is possible?