When infants are tested with stimuli of various chromaticities embedded in a dark or achromatic (white) surround, they show maximal preference for stimuli of maximal colorimetric purity, and minimal preference for achromatic stimuli. We investigated how this pattern of preferences changes with changes of surround chromaticity. Sixteen-week-old infants were tested in two experimental conditions. The surrounds in the first condition were red and white; and in the second condition green and white. The three test stimuli varied in colorimetric purity from white to red in the first condition, and from white to green in the second condition. A test stimulus that appeared achromatic to adults when viewed in the chromatic surround was included. Infant spontaneous looking preferences changed with changes of surround chromaticity. The changes were consistent with the conclusion that infant looking behavior is governed by a preference for the stimuli that differ maximally in purity from the surround. The implications of this pattern of results are discussed.