Compositions are disclosed that impart one or more durable hair styling benefits. The durable styling compositions comprise at least a first compound having anhydride, diacid, diester, or half-acid/half-ester functionality, and a second compound having at least one amine moiety or hydroxyl functional group. In one embodiment the durable styling composition takes the form of a leave-in product. The durable styling compositions are heat-activated, which may be accomplished through the use of a heated styling tool like a flat-iron, curling iron, and/or hair dryer. The benefits include shine, conditioning, softness, defrizzing, and improved hair alignment, and endure for up to 5 wash cycles or more without having to reapply the durable styling composition nor heat.
