Lt. Gov. Anthony G. Brown (D) during hte 2010 campaign. (Photo by Aaron Davis/The Washington Post)

Brown, who is gearing up to run for governor in 2014, announced the departure Thursday, praising Adams for being “an invaluable member of our team.”

Adams has been a constant presence in an office that has seen a lot of turnover since Brown arrived as lieutenant governor in 2007. After an initial stint as deputy chief of staff, Adams was elevated in December 2008 to his current position.

“While it is always difficult to lose a dedicated public servant like Earl, I understand that I have been lucky to have him at my side for so many years, and I wish him and his family the very best,” Brown, a former delegate from Prince George’s County, said in a statement.

Adams, who has one young child and another on the way, said it has been an “absolute honor” to work for the lieutenant governor and that he will “always value the time I have spent working with Anthony Brown.”

Adams, a lawyer, is joining the Baltimore office of DLA Piper.

Brown’s office said that Maia Estes, his deputy chief of staff, will be elevated on Jan. 6 to interim chief of staff.