Hair restoration includes the medical and surgical treatment of various forms of hair loss, including non-surgical. The most common cause of hair loss is androgenetic alopecia (AGA), also known as male pattern baldness or female pattern baldness.
Medical hair restoration
Propecia (Finasteride) is approved for medical hair restoration for men with AGA. http://www.accessdata.fda.gov/scripts/cder/drugsatfda/index.cfm?fuseaction=Search.DrugDetails Minoxidil is approved for treatment of men and women with AGA.
Hair transplant surgery
Surgical hair restoration is the only permanent technique that can move hair from permanent zone to the balding area. Hair restoration surgery is a procedure where natural groupings of 1 to 4 hairs, called follicular units, are extracted from the patient's donor site then moved to the area of balding, called the recipient area. Hair restoration surgery, or hair transplantation has been traditionally used for the treatment of male patterned baldness, but it has gained popularity for treatment of female patterned baldness, eyebrow hair loss, and to restore hair in any part of the body. In addition to cosmetic purposes, hair restoration can be used for treatment of hair loss due to trauma or burn. Hair restoration should be performed by certified surgeons, who specialize in hair replacement. The International Society of Hair Restoration Surgery  is a medical association of physicians who specialize in hair restoration.
Follicular Unit Transplantation
The most common hair restoration surgery technique is Follicular Unit Transplantation (FUT). In FUT, follicular units are extracted from the back of the head, where hair tends to be more permanent, in a strip of skin called the donor strip. Once the strip is removed, the donor area is either sutured or stitched back up, ideally in a way that minimizes scarring. Removing adequate width of strip helps with minmizing the scarring. Measurement of scalp laxity with a Laxometer can help a hair transplant surgeon remove the strip with the optimum size. If done properly, the remaining scar, called a line scar, will only be visible with short-cropped hair or a shaved head. After the donor strip is extracted, it is dissected into individual follicular units. These are then transplanted into the recipient area in the patient s balding scalp where they become viable hair-producing follicles.
Follicular Unit Extraction
In Follicular Unit Extraction (FUE), follicular units are extracted from the back of the head using a surgical punch or other device. A 1-mm punch is often used to make a small circular incision in the skin around the upper part of the follicular unit, which is then extracted directly from the scalp. Once removed, the donor follicles are transplanted into the recipient area where, as in FUT, they grow hair.