A method for shaping keratin fibres comprising: providing a crosslinking composition, wherein the crosslinking composition comprises: an active agent, wherein the active agent comprises at least two functional groups selected from: &mdashC(OH)&mdash and &mdashC(&boxHO)OH and wherein if the active agent has three or more &mdashC(OH)&mdash groups, then the active agent has 4 or more carbon atoms and wherein no 1 carbon atom is functionalized with more than one functional group and wherein the active agent has a molecular weight of 500 g/mol or less a photocatalyst a cosmetically acceptable carrier and applying the crosslinking composition to keratin fibres, mechanically shaping the keratin fibres with an appliance or implement, and exposing the composition to electromagnetic radiation having a wavelength of from about 300 nm to about 750 nm Also a related composition, use, kit and process.
