In May 2015, Flack received an honorary Doctor of Fine Arts degree from Clark University, where she gave a commencement address.

Speed Art Museum in Louisville, Kentucky, organized a retrospective of her work, and Flack's pioneering efforts into the world of photorealism popularized the genre to the extent that it remains today.

[6] She earned a graduate degree and received an honorary doctorate from Cooper Union in New York City and a Bachelor of Fine Arts from Yale University.

[12] The critic Graham Thompson wrote, "One demonstration of the way photography became assimilated into the art world is the success of photorealist painting in the late 1960s and early 1970s.

[22] In 2023 her work was included in the exhibition Action, Gesture, Paint: Women Artists and Global Abstraction 1940-1970 at the Whitechapel Gallery in London.

Flack's work brings in everyday household items like tubes of lipstick, perfume bottles, Hispanic Madonnas, and fruit.

Flack often brought in actual accounts of history into her photorealist paintings, such as World War II' (Vanitas) and Kennedy Motorcade.

Her sculptures often demonstrate a connection to the female form, including a series of diverse, heroic women and goddess figures.

The statue, which would have been roughly the height of a nine-story building, was meant to be installed on the East River shore in the Hunters Point area of Long Island City, across from the United Nations Headquarters.

[26] The project was never fully realized, however, as protestors in the mid-late 1990s objected to Queen Catherine's ties to the Transatlantic Slave Trade.

)[27] Flack nevertheless remained dedicated to the project, and notes that she endeavored to depict Catherine as biracial, reflecting her Portuguese background and paying homage to the ethnic diversity of the borough of Queens.