A reshapable hair styling composition comprising, in a cosmetic vehicle appropriate for hair, at least one dispersion comprising at least one polyurethane in a water and/or solvent medium, said at least one polyurethane being obtained by reacting: (a) an isocyanate terminated polyurethane prepolymer being obtained by reacting: (i) at least one polyactive hydrogen compound insoluble in the medium of the dispersion, wherein said polyactive hydrogen compound is chosen from alkyl, aryl, and aralkyl structures optionally substituted in and/or on the structure by N, O, and/or S groups; (ii) at least one polyisocyanate, and (iii) at least one polyactive hydrogen compound soluble in the medium of the dispersion, (b) at least one polyfunctional chain extender; and (c) at least one chain terminator.