From 1971 to 1980 Freedman was the president of City Walls Inc., a not-for-profit organization, established in 1969 which worked with artists and communities to revitalize New York City through public art and had sponsored more than fifty murals. In 1971, she founded the Public Arts Council; “both organizations provided technical assistance and financial support for a wide variety of projects, and developed programs to explore the potential of urban public spaces”. In 1977 she founded the Public Art Fund of the City of New York by merging City Walls and the Public Arts Council.
Freedman served as New York City's first Director of Cultural Affairs during the Lindsay Administration, and as President of the Municipal Art Society. Greatly through her efforts New York City introduced Percent for Art legislation in 1982, which requires civil construction projects to spend a portion of their budgets on art.
One of the entrances of Central Park in Manhattan, located at the southeast corner of the Park at 60th Street and Fifth Avenue is called The Doris C. Freedman Plaza in her honour. It is the site of rotating sculptural art installations presented by the Public Art Fund.
In 1982 the Doris C. Freedman Award, dedicated to her memory was established by Executive Order by Mayor Edward I. Koch. The Award honours “an individual or organization for a contribution to the people of the City of New York that greatly enriches the public environment”.