Boston-based Samuels & Assoc. is joining the development team for Washington Village, a $400 million project at 235 Old Colony Ave. in South Boston that’s yet to break ground since gaining final approvals in 2016.

The site spanning 5 acres near Andrew Square is approved for 656 condominiums and apartments and 100,000 square feet of retail space.

“Samuels & Assoc. will bring its considerable expertise in residential community development, placemaking, and project management to the table in support of this dynamic, mixed-use project,” the firm said in a statement. The company declined to comment on additional details, but said it will work with the city and neighborhood groups to move the nearly 1-million-square-foot project forward.

Samuels is the latest major development firm to invest in the industrial corridor on the western edge of South Boston, which is being eyed for higher-density multifamily and commercial projects. Newton-based National Development recently acquired a group of parcels on Dorchester and Old Colony avenues for $110 million, and is expected to make additional purchases in the neighborhood.

Samuels & Assoc. led the transformation of the Fenway neighborhood with development of luxury residential towers such as Pierce Boston and new class A office space in projects including the Van Ness and the ongoing redevelopment of the Landmark Center property.

Boston-based Core Investments, led by David Pogorelc, began assembling the Washington Village parcels in 2010, beginning with a 2-acre industrial property acquired at a foreclosure auction. Pogorelc later bought properties occupied by a transmission shop and commercial laundry and helped the owners relocate their operations.

Designed by Prellwitz Chilinski Assoc., Washington Village will consist of nine buildings ranging from 3 to 21 stories. Some 17 percent of the units will be income-restricted, including 4 percent in the workforce housing category for households that earn 120 to 170 percent of the area median income. Core Investments previously said more than 400 units will be sold as condos.