Massachusetts State Senator Ben Downing will not seek re-election this fall. The Pittsfield Democrat says he promised himself he wouldn’t serve more than ten years when he first ran for office.

“While I don’t think the work is by any means done, I think we’ve made a lot of good progress, and I felt like personally it was time for a change for me,” Downing says.

Downing plans to finish out his two-year term. He says he’ll likely look for work in the private sector but hasn’t decided his next step.

“I’d like to see what else is out there in the big, bright world, and find another way to contribute,” Downing says. “The only thing really that I’ve ruled out at this point is, I don’t want to lobby. There are plenty of good people who do that, but it’s just not for me.”

Downing was first elected in 2006 at age 25, beating four other candidates in the Democratic primary and two opponents in the general election. He’s run unopposed in every election since.

Downing says he’s most proud of his work to expand solar energy, and on a transgender rights bill passed in 2011. He says he hopes to see action on a bill expanding public accommodation rights to transgender people.

State Senate President Stan Rosenberg, an Amherst Democrat, released a statement calling Downing “a progressive leader” whose “voice will truly be missed.”

“He has made a real difference for working families in Massachusetts, and I know that he will bring the same energy, intellect, and passion he exhibited in the legislature to his future endeavors,” Rosenberg said.

New England Public Radio’s Sam Hudzik contributed to this report.