Mark Groen <markgroen at telus.net> typed: > An overview of the basics of credit card verification: > http://www.webdevelopersjournal.com/articles/card_fraud.html > There's quite a few php scripts out there I think for simply verifying the > numbers - an example: > http://php.resourceindex.com/detail/00597.html > You can make sure it is a well formed number client side also with > javascript: > http://javascript.internet.com/forms/val-credit-card.html Thanks, Mark; but we need to do more than simply run the LUHN algorithm. I guess what I'm looking for is information about connecting to a payment service like Cybercash or authorize.net, using our own hand-rolled script instead of a pre-packaged shopping cart. charles johnson lgf web design http://littlegreenfootballs.com