Abstract 1. A substitution method is described for measuring, with a microsolarimeter, reflectances for solar radiation of the coats of comparatively large live animals. The measurements were made in 8 positions round the trunk. From these measurements a mean reflectance, weighted for variations in incident radiation, was calculated. 2. Reflectance measured on Jersey heifers, water buffalo calves and adult Merino sheep had a standard deviation from the mean for pairs of estimates varying from 0·01 to 0·04 according to the position on the trunk. The standard deviation for the weighted mean reflectance was 0·01. 3. It is shown that on an animal of uniform colour the reflectance is greater for positions receiving radiation reflected by the ground than for those receiving direct solar and sky radiation.