On Thursday, John Griffin was announced as the successor to Matthew Gallagher, who left to head up a philanthropic organization.
Griffin has served as DNR secretary since 2007.
He previously held the job from 1995-1999 under then-Governor Parris Glendening. He has also led the Washington Suburban Sanitary Commission.
O’Malley says Griffin “has been at the heart and soul of Maryland’s environmental agenda.”
Griffin says he’s very excited about the chance to serve as the governor’s chief of staff.