Abstract: In accordance with one embodiment of the invention, a set of web services is provided that allow a client application to display product information from a site catalog, add/update/delete those products into a shopping cart hosted on the client, and have that shopping cart also maintained at a central hosted site. As such, the user is directed to the central hosted site in order to complete payment and fulfillment of the order. Several companies desire this functionality. As such, a set of shopping cart application programming interface (API) can be built and used to access product information and prices as well as to add or remove products from the shopping cart to which the consumer will be redirected upon finalizing the purchase. These processes are conducted in real time.