Hair restorative compositions useful in repairing damaged hair include at least one hair shaft bonding agent dispersed within an appropriate solvent or carrier, such as water. When applied to damaged hair, the hair shaft bonding agent adsorbs into and bonds to the damaged hair shaft, filling in discontinuities and adhering split ends or loosened cuticle layers back together within the main hair shaft. A wetting agent may be included to facilitate absorption and bonding of the hair shaft bonding agent to hair. A thickening agent may be included to yield a hair restorative composition that is much easier to apply compared to runny compositions having the consistency of water. A conditioner may be added to nourish and condition the hair. The inventive hair restorative compositions are able to permanently repair damaged hair, thereby resulting in hair that is stronger, healthier, and more resistant to further damage.