A hair colouring composition comprising: a) dihydroxyacetone or a derivative thereof b) from 0.2 to 10 wt % of the total composition of a cationic conditioning compound c) a sulphonic compound of formula: H2N—(CHR1}pS(—X)q—Y in which where p is an integer from 1 to 5, R1 is H or an alkyl group, X is O or S q is an integer from 0 or 1. Y is an alkyl group or hydroxyl group.
