In 1948, he pioneered the use of Magna paint—a newly developed oil-based acrylic paint made for him by his friends, New York paintmakers Leonard Bocour and Sam Golden.

During the 1950s he and a group of artists that included Kenneth Noland, Gene Davis, Thomas Downing, Howard Mehring, Anne Truitt and Hilda Thorpe among others were central to the development of Color Field painting.

They continued in a tradition of painting exemplified by Jackson Pollock, Barnett Newman, Clyfford Still, Mark Rothko, Robert Motherwell, and Ad Reinhardt.

Louis characteristically applied extremely diluted, thinned paint to an unprimed, unstretched canvas, allowing it to flow over the inclined surface in effects sometimes suggestive of translucent color veils.

In 1954, Louis produced his mature Veil Paintings, which were characterized by overlapping, superimposed layers of transparent color poured onto and stained into sized or unsized canvas.

[6] The Veil Paintings consist of waves of brilliant, curving color-shapes submerged in translucent washes through which separate colors emerge principally at the edges.

These were followed by Florals and Columns (1960), Alephs (1960), Unfurleds (1960–61)—in which rivulets of more opaque, intense color flow from both sides of large white fields of raw canvas—and finally the Stripe paintings (1961–62).

In 2024, both Beth Shin and Delta Eta, integrated Every Sound Is a Shape of Time: Selections from PAMM's Collection, at the Pérez Art Museum Miami.

[12][13] In 2015, a striped canvas by Louis, Number 36 (1962), from the collection of Lord Anthony and Lady Evelyn Jacobs sold for £1.5 million at Christie's London.