SANFORD — The Sanford School Committee has named Matthew Nelson as the new superintendent of schools effective Jan. 1.

Nelson will replace Superintendent David Theoharides as he retires from the position he has held since 2011.

The School Committee also named Steven Bussiere as assistant superintendent.

Nelson has been Sanford’s assistant superintendent since December 2015.

Prior to coming to Sanford, Nelson served as principal at Westbrook Middle School for five years. He also served as athletic director for the Westbrook School Department, guidance counselor at Bonney Eagle High School in Standish and was named 2014 Middle School Principal of the Year by the Maine Principal’s Association.

Nelson earned his bachelor’s degree in Communication and Business from Saint Joseph’s College in Standish, and his master’s degree in School Counseling from the University of Southern Maine.

Steve Bussiere has been part of the Sanford School Department team since September 1999, working first as a classroom teacher and then as a teacher leader before joining the administration team at Carl J. Lamb Elementary School in 2006.

His credentials include a bachelor’s degree, a master’s degree in teaching and a Certificate of Study from the University of Southern Maine.

“I am very excited to have Matt and Steve assume leadership of our schools; their familiarity with our community, their leadership skills and their enthusiasm will serve our students, staff and community well,” said Sanford School Committee Chairman John Roux.

Roux also extended his appreciation to Superintendent David Theoharides, who is retiring after 42 years in education in Maine.

Theoharides will continue to assist the district as it finalizes the high school construction project.