When planning three New Deal-era green suburbs, government officials were unable to coax privately-owned businesses to open stores in the prospective center city shopping complexes. The co-op concept was adopted. The very first co-op endeavor, the GREENBELT CENTER Co-op Food Store, began business December 15, 1937. Today, it is the sole green suburb co-op store still in business.
Graphic from Greenbelt Consumer Services

Here we see the original GREENBELT CENTER Co-op Food Store. This snapshot, and the two that follow, were taken between January and September of 1938. 
Photo from Library of Congress / Marion Post Wolcott 

Originally, all businesses in GREENBELT CENTER were operated by a non-profit organization headed by Edward Filene, of Boston's Filene's department store. 
Photo from Library of Congress / Arthur Rothstein

In January 1940, Greenbelt's stores became a community-run enterprise. Stores in the Greenhills and Greendale developments were community-run from the start.
Photo from Library of Congress / Russell Lee

By the late 1940s, the Co-op Food Store was so successful that it needed larger quarters. A new store was built adjacent to the existing East Building of GREENBELT CENTER. The new grocery opened its doors in November 1948. In this snapshot, the new store -at the center of the photo- is seen as it appeared in the early 1950s.
Photo from www.greenbeltmuseum.org

By 1959, the GREENBELT CENTER grocery was promoted as the Co-op Superstore. It was now one in a chain of eight locations, with branches in Wheaton, Rockville, Silver Spring, Takoma Park and Westminster (in Maryland) and Fairlington and Falls Church (in Virginia). 

Graphic from Co-op Superstores

The GREENBELT CENTER Co-op Superstore was gutted by fire in April 1962. The structure was rebuilt and re-opened, as the Co-op Supermarket Pharmacy, in October 1962. The store remains in business to this very day.
Photo from Library of Congress / James W. Rosenthal