A longtime urban preservationist, civic activist, and author, Margot Gayle (née McCoy) was born in Kansas City, Missouri, on 14 May 1908. Moving frequently as a child as a result of her father's vicissitudes in the automobile business, Gayle attended the University of Michigan. Subsequently, she moved to Atlanta, began work as a social worker, and earned a master's degree in bacteriology from Emory University. Marrying accountant William T. Gayle, Margot contributed to the United States's World War II effort as a volunteer publicizing civil defense efforts. Next moving to New York City, Gayle inaugurated a variegated career that would include radio script writer, freelance magazine scribe, and public relations entrepreneur. Later she held public relations positions in city government; most important, she wrote a weekly architecture column in the Daily News for sixteen years. Producing two daughters, Carol Gayle and Gretchen Gayle Ellsworth, Gayle's marriage nonetheless ended in divorce in 1957, the same year she joined the Samuel J. Tilden Club, a Democratic Party reform group. The indefatigable Gayle also ran, albeit unsuccessfully, for City Council.

Notwithstanding her political activities, in 1957 Gayle spearheaded efforts to "save" the four stalled clocks adorning the Jefferson Market Courthouse, a brick and stone structure erected in the 1870s on 6th Avenue. Gayle's group succeeded by 1959 in convincing Mayor Robert Wagner to remove not only the clocks but perforce the building as well from the auctioneer's block. Moreover, Gayle's intrepid leadership netted a number of followers, including writers Jane Jacobs and Lewis Mumford and poet e.e. cummings. By 1961, the group succeeded in restarting the building's clocks; in 1967 the courthouse itself reopened as a public library. Her appetite whetted by the courthouse rescue, Gayle lobbied for a landmarks preservation law, which the city enacted in 1965. In 1966, impelled by the demolition of Pennsylvania Station, Gayle helped to establish the Victorian Society in America, a national non-profit organization committed to preserving the United States's nineteenth century heritage. Most important, she founded the Friends of Cast Iron Architecture in 1970, a group focused on the preservation of Victorian-era iron-fronted buildings. The group succeeded in opposing a proposed Lower Manhattan expressway in 1971 and in 1973 they won the establishment of the twenty-six block SoHo Cast Iron Historic District, which preserved buildings and artifacts and on the whole prevented SoHo from experiencing large-scale urban renewal. Gayle went on to fight to preserve cast-iron buildings around the country, as well as street clocks and lamp posts in New York City until her death in 2008 at the age of 100.