Attorney Mark O'Connor has been practicing law since 1986 in Medford, Massachusetts. For the past 18 years, he has worked as a sole practioner with concentration in the areas of real estate, personal injury, wills and trusts, civil litigation, family, business and probate law. He has a second office in Tewksbury, Massachusetts for the convenience of clients in the Merrimack Valley region, and, in 2006, he became admitted to the practice of law in the State of New Hampshire.

Attorney O'Connor is a member of the Massachusetts and New Hampshire Bar Associations. He is a recipient of a Pro Bono Award from the Volunteer Lawyers Project.

Outside the office, Mark O'Connor serves as a volunteer with T.H.E. Farm, a therapeutic riding program, and referees youth and high school soccer. He previously served as a board member and coach with the Tewksbury soccer and basketball leagues and as an elected library Trustee.

Attorney O'Connor graduated from Williams College in 1982 and Suffolk University Law School in 1986.