The present disclosure relates to hair care compositions for chemically treating hair, to kits comprising the compositions, and to methods for treating hair with the compositions. The compositions include one or more polymeric acid compounds and/or polymeric acid anhydride compounds in addition to one or more active agents for chemically treating the hair. Additionally, the compositions can optionally include one or more non-polymeric, mono-, di-, and/or tri-carboxylic acids and/or one or more mono- and/or di-amines and/or polyamines. Hair treated with the compositions exhibits improved softness, smoothness, and discipline.
