The preparation for permanently deforming hair has a pH of 6.5 to 9.5 and contains, as keratin-reducing agent, a 2-mercaptopropion-amide of the formula (I): ##STR00001## in which R.sub.1 and R.sub.2, independently of one another, represent H, a linear or branched alkylaminoalkyl group with 2 to 8 carbon atoms, or a morpholinoalkyl group with 2 to 3 carbon atoms in the alkyl portion of the morpholinoalkyl group, with the proviso that R.sub.1 and R.sub.2 are not simultaneously H, or that R.sub.1 and R.sub.2, together with the nitrogen atom, form a five-or six-membered heterocyclic ring, which optionally contain an additional N or O and are optionally substituted with one or two OH and/or methyl groups.
