The American Express firm, also known as Amex, is a worldwide financial services firm and bank holding company based in the United States that focuses on payment cards. Its headquarters are located in Lower Manhattan's Battery Park City area at 200 Vesey Street, popularly referred to as the American Express Tower.
American Express's merchant and bank partner network, Global Merchant & Network Services (GMNS), acquires and manages connections with banks and businesses that accept American Express-branded cards.