Dan Flavin began using fluorescent light as an art material in the early 1960s. Although he was limited to lengths and colors of fluorescent tubes that were commercially available, the unique properties of light opened up many new visual possibilities. Rather than explore the interactions of color within the two-dimensional plane of a painting, Flavin could now mix his colors in space, taking advantage of the way emitted light fills architectural interiors as it reflects off of walls, ceilings, and floors. Untitled is part of a series of works that Flavin dedicated to his friend, the abstract painter Barnett Newman (1905–1970). More than 25 years earlier in the 1960s, Newman had made a series of paintings in which he used only the three primary colors—red, yellow, and blue. As a pun on the popular 1962 stage play and film Who’s Afraid of Virginia Woolf?, Newman titled his series Who’s Afraid of Red, Yellow and Blue. The strictly defined parameters that Flavin set for himself using red, yellow, and blue fluorescent tubes recall the older artist’s efforts to break artistic ground with the basic visual elements of primary colors and line.