A hair transplant involves removing small patches of hair-bearing scalp from the back and sides of the head and transplanting them to bald or thinning areas. The procedure has been performed since the 1930s but improved in the 1950s. Different sized grafts - ranging from single hairs to groups of 30-40 hairs - can be used. Multiple sessions may be needed over 1-2 years to achieve fullness. It is important to carefully choose a skilled surgeon to achieve natural-looking, lifelong results.