BROOKFIELD, Wis. – Fiserv's ACCEL/Exchange ATM and EFT network, which has 1,400 participating credit unions, has announced the addition of 14,000 Exxon Mobil service stations to its debit and ATM network. Fiserv said ACCEL/Exchange is currently the nation's fifth largest PIN-debit network, with 1.6 million point-of-sale terminals and 55,000 ATMs across the country. "Getting cardholders authorized at merchant POS terminals through our cost-effective and efficient online debit network is our goal, plain and simple," said Tony Catalfano, CEO of Fiserv EFT, the Fiserv business unit that operates the ACCEL/Exchange Network. "ACCEL's switch provides a first-rate authorization endpoint. We are thrilled to add ExxonMobil to our growing list of participating merchants."