Construction is under way one one of the largest recent developments in Cambridge’s Central Square, the $190-million Mass+Main including 308 market-rate and affordable units.

Twining Properties and MassPRIM are partnering on the 308,000-square-foot development in three buildings built in phases through mid-2020.

The project, including 17,000 square feet of retail space, involves demolition of four buildings and construction of two new buildings, including a 19-story tower, and redevelopment of an existing historic building at 411-413 Massachusetts Ave.

“The affordable housing and mixed-income elements of this development give families an opportunity to stay and live in Cambridge,” Massachusetts State Treasurer Deb Goldberg said at a groundbreaking last week.

CBT Architects designed the complex to LEED Gold standards including green roof terraces and wind power, car and bike sharing stations and electric vehicle charging stations.