Serve is an online payment system similar to PayPal introduced on March 28, 2011.[1] The service is provided by American Express and available at serve.com. The service allows users to transfer money to other users, shop online, and shop in stores with a card. The card is accepted at all AMEX locations. Card members can also use their cards to withdraw money from ATMs. Currently, Serve is only available to residents of the United States.