In 1920 Marshall began a campaign to raise funds for a national conservancy which would include negro music. In April 1921 the Conservancy produced a program for a fundraiser that covered periods of "negro music and drama" in New York. Marshall returned to the pursuit of a national conservancy in April 1922, calling together various leaders in black music and a followup production of the "negro music and drama" was scheduled for May. Walter Damrosch was listed as specifically supporting the idea of the national conservatory. A Conservancy student recital followed in May. Broader recognition of respect for negro music was summarized including Marshall's work in 1922. Marshall was approaching having something for a national conservancy set up in New York by May 1924, but instead she went to Haiti with her husband's work, making a brief return trip in August, as he was appointed to a commission to investigate abuses during the United States occupation of Haiti. They returned by February 1927. By 1934 Marshall was acknowledged as director of the Conservancy again.