Gregg L. Hartley is the Vice Chairman & Chief Operating Officer of Cassidy & Associates, a Washington D.C lobbying firm. according to a biographical note he "directs the firm’s Communications and Media Practice and leads teams serving agri-business, commerce and financial services clients." 
Prior to joining the company Hartley worked for 18 years as an advisor to the Republican U.S. House of Representatives Majority Whip Roy Blunt. "As Chief of Staff to the Whip, he was one of a small number of aides who worked closely with the Speaker, Majority Leader, Conference Chair, and seven other leadership offices," a biographical note states. 
- "Gregg L. Hartley Vice Chairman & Chief Operating Officer", Cassidy & Associates, accessed January 2006.
- Josephine Hearn, "Ex-Blunt aide spreads wings on K St. - Gregg Hartley’s stellar contacts set him apart", The Hill, November 18, 2003.