As a second generation Abstract Expressionist, Frankenthaler was strongly influenced by the work of Gorky, Pollack and de Kooning, yet she sought a unique means of personal expression. The breakthrough occurred in 1952, after a summer spent painting watercolors in the Canadian Maritimes. These paintings, abstract landscapes of the Nova Scotia coast, inspired an unconventional merging of the fluid translucency of watercolor with the gestural qualities of Abstract Expressionism.

Working on the floor of her New York studio, Frankenthaler devised a unique technique using oil paint thinned to a watery consistency and alternately pouring and dripping the paint onto an unsized, unprimed canvas. As paint and plaster become one in the ancient technique of fresco, Frankenthaler's technique fused paint and canvas into a single entity. Frankenthaler's masterpiece Mountains and Sea, was completed in a single day, October 26, 1952.

The diaphanous clouds of color that have become the artist's signature and her revolutionary soak-stain technique became the catalyst for a generation of color field painters, notably Morris Louis and Kenneth Noland.

Frankenthaler has had numerous solo exhibitions throughout the world, including the Whitney Museum in 1969 and the Metropolitan Museum in 1973. She was also awarded a Doctorate of Fine Arts from Smith College in 1973 and is an elected member of the National Institute of Arts and Letters.