Helen Frankenthaler (New York, NY, 1928 – Darien, CT, 2011) transformed the relationship between pigment and support, pouring paint thinned nearly to the consistency of water onto raw, unprimed canvas so that color soaked directly into the fibers rather than sitting on a painted surface, eliminating the traditional distinction between image and ground.

She arrived at this soak-stain technique with Mountains and Sea (1952), a canvas built from pale washes of color that critics recognized immediately as a departure from the thick impasto of her Abstract Expressionist elders; the method was never purely accidental, "you have to know how to use the accident," she said, "how to recognize it, how to control it." The technique influenced her contemporaries Morris Louis and Kenneth Noland, and her work was included in Clement Greenberg's 1964 exhibition Post-Painterly Abstraction, though Frankenthaler's own compositions, built through editing, layering, and deliberate decisions about where a pool of color should stop, resist the more mechanical readings that exhibition later encouraged.