Mary Stillman Harkness

Mary Stillman Harkness or Mary Harkness (1874 – 1950) was an American art collector and noted philanthropist.

Harkness was the daughter of a prominent New York lawyer. Her mother was the heiress of several generations of Connecticut farmers. She married Edward Harkness in 1904, the wealthy heir of an early investor in Standard Oil. Two years later she was involved in a car accident with her father, who did not survive. Perhaps that is why the couple did not have children, but they continued philanthropic work that Edward had started before their marriage. After his early death in 1940 she spent the rest of her life making donations to various institutions until her death in 1950.

Harkness died in New York City and her will divided her wealth and property in various places she had frequented with her family. She is best known for Harkness Memorial State Park, where her summer home Eolia, which the couple bought from Mary's sister Jessie and her brother-in-law, William Ambrose Taylor in 1907, preserves the memory of her work. Harkness supported the founding of Connecticut College as a women's college in 1911, after Wesleyan University decided it would admit only men, and she made a number of significant gifts to the college in the 1930s. Wesleyan did not admit women until 1976.

Mary Harkness was a member of the American Museum of Natural History, New York Botanical Garden, the Garden Club of America, the English-speaking Union, and New York Philharmonic Society.