Cosmetic compositions comprising water at least one estolide ester compound of Formula (3) wherein n is from 1 to 10 preferably from 2 to 8 and R is selected from branched or linear C alkyl and B) optionally at least one surfactant component B C) optionally at least one thickener component C D) optionally at least one hair conditioning component D and E) optionally at least one further component E different to A to D can be used for improved hair treatment.