Devaney began his career serving as the director of pro personnel under Bobby Beathard during his time with the San Diego Chargers from 1990 to 2000. He also worked a brief stint with the San Francisco 49ers for three seasons. Devaney then worked with the CBS pregame show for two years. In 2006 Devaney began working as an assistant to Rich McKay, president and former general manager of the Atlanta Falcons from 2006 to early 2008. In February 2008 the St. Louis Rams hired him as vice president of pro personnel to help conduct their 2008 draft. He was promoted to general manager of the Rams on December 24, 2008. He made his first major hire as the Rams' general manager on January 17, 2009, when the Rams announced that Steve Spagnuolo would be its new head coach. Since the hiring he had revamped the entire front office of the Rams. He was fired at the end of the 2011 season after a 10-38 record as GM.
↑Garafolo, Mike. "Monmouth County's Billy Devaney now making waves as GM of the St. Louis Rams", The Star-Ledger, April 21, 2009. Accessed July 20, 2011. "'He's very happy right now. And I can tell he is, too,' said Mike Corley, Devaney's best friend from before their days together at Mater Dei High School in New Monmouth.... It was a fitting career path for a self-proclaimed "draftnik" (before there were draftniks) who used to take the bus from Leonardo -- a section of Middletown -- to Port Authority in Manhattan to pick up a copy of Street & Smith's draft guide."