We previously found that untrained subjects make nonrandom color matches to odors and that the color matches are stable over time (Gilbert, Martin, & Kemp, 1996). Here we investigate further aspects of the cross-modal associations between vision and olfaction: whether perceptual dimensions of odor vary systemically with those of vision. Subjects matched Munsell color chips to five odors presented at three concentrations; they also rated odor intensity. Significant negative correlations between Munsell value and perceived odor intensity were found for three odors. The results suggest that stronger odors were associated with darker colors. The cross-modal relationship between vision and olfaction appears to be dimensional: Color lightness varies inversely with perceived odor intensity. This finding parallels the dimensional relations found between other modalities (e.g., lightness varies with loudness).