Thompson Square Partners is a commercial real estate development company which was started by James F. DeVellis in 1992. The portfolio has grown over the last 25 years to include several pieces of retail property. The flagship property is in Charlestown at 1 Thompson Square. The building was built in 1872 and historically housed the Charlestown Five Cents Savings Bank and also was the home of the free masons temple in the early part of the twentieth century. The building has undergone an extensive renovation in 2017.