Abstract: An inverse emulsion copolymer composition comprises (A) an aqueous phase comprising a cross-linked hydrophilic polyelectrolyte copolymer (A?) obtained by the free radical copolymerisation of: (i) at least one anionic ethylenically unsaturated monomer bearing a negatively charged group and one polymerisable C?C double bond, or at least one cationic ethylenically unsaturated monomer bearing a positively charged group and one polymerisable C?C double bond, and (ii) at least one non-ionic ethylenically unsaturated cross-linking monomer bearing at least two polymerisable C?C double bonds, and (iii) optionally, one or more hydrophilic non-ionic ethylenically unsaturated monomers bearing one polymerisable C?C double bond, (B) an oil phase comprising a carrier oil (C), (D) (i) at least one water-in-oil emulsifying surfactant, and (D) (ii) at least one oil-in-water emulsifying surfactant; characterised in that the carrier oil component (C) of the oil phase comprises from 75% to 100%, by weight of the said carrier oil