Methods, formulations, and kits for curling and/or preventing damage in the curling of hair are disclosed herein. Treatment with one or more hydroxide-containing agents in combination with one or more active agents can reshape hair, without the need for sulfur-containing reducing agents. To impart curl to hair, the active agent(s) and the hydroxide-containing agent(s) are applied either as a combined formulation or as separate formulations which are applied simultaneously. Use of the active agent along with a hydroxide-containing agent allows the level of curl imparted to hair to be controlled, as compared to the natural amount of curl, if any, in the untreated hair.
