A survey of 600 stray cats from industrial-urban areas of Adelaide was conducted and the frequencies of some genes controlling coat colour were determined. The sample fitted a I : 1 sex ratio and comparison of observed and expected phenotypes at the orange locus established that the population was panmictic. The frequencies for d (0·326) and S (0·295) were significantly different from those in another area in Australia. A possible reason for this difference, based on different human population origins and preferences, is proposed. The frequencies of /, a, W, tb , and 0 did not differ greatly from those in other areas in Australia.