GREENFIELD — Big Brothers Big Sisters of Franklin County and Big Brothers Big Sisters of Hampden County are merging into one organization to streamline some of their operations.

The mentorship agencies, both founded in 1967, will become the largest mentorship organization in the region and will go by the name Big Brothers Big Sisters of Western Massachusetts. David Beturne, who is executive director of the Hampden County agency and was named interim executive director in Franklin County in April, will lead the new entity.

Beturne said the merger has been in the works since the summer.

“We both have two award-winning agencies, we have great staff and we’d already done a lot of collaborations together anyway,” he said. “From our board of directors, our staff, our volunteers, the feedback we’ve gotten has been pretty positive.”

Beturne said the Big Brothers Big Sisters office at 16 Court Square in Greenfield will remain in use and changes to the agency’s operations will be minimal.

“All the systems behind the organization are the same,” he said, adding that the only differences will be “behind the scenes, operational, HR kind of stuff.”

Beturne said the agency will employ the same 13 people and no jobs were lost during the merger. In fact, there are plans to expand services to Berkshire County and hire a chief growth officer for that purpose. Beturne said each county will have an advisory council as well as representation on the organization’s board of directors.

There are plans to eventually merge the agencies’ websites and social media accounts. The merger does not include the Center for Human Development’s Big Brothers Big Sisters program, which will continue to serve the Hampshire County area.

Beturne said the merged agency has about 325 active matches (pairs of mentors, called “Bigs” and mentees, called “Littles”) and new volunteers are always needed.

Reach Domenic Poli at: dpoli@recorder.com or 413-930-4120.