The aim of this work was to investigate how efficiently colour information is distributed, in a least-redundancy sense, across the variables of a colour space, and how this distribution varies across different colour spaces. It was found that among the physiological and psychophysical colour spaces tested, Derrington-Krauskopf-Lennie space was the most efficient, although this result is contingent on assumptions about the pre-processing of cone signals. Among the colorimetric spaces tested, CIECAM02 was the most efficient. For most spaces, the variables associated with chromatic properties carried more information than the variables associated with achromatic properties.