Before FS-ISAC, a non-profit association dedicated to protecting financial services firms from physical and cyberattacks, Bill Nelson in 2009 was elected Vice Chairman of the ISAC Council, a group dedicated to sharing critical infrastructure information with the government and across key sectors. From 1988 to 2006, Nelson served as Executive Vice President of NACHA - The Electronic Payments Association. While at NACHA, he oversaw the development of the ACH network into one of the largest electronic-payment systems in the world, processing nearly 14 billion payments in 2005. He also oversaw NACHA's rule-making, marketing, rules enforcement, education and government relations programs. Prior to joining NACHA, he held several treasury management and lending positions within banking.