The available treatment modalities for hypertrophic scars and keloids have very little success. Surgical treatment of these lesions without adjuvant therapy is also associated with high recurrence rate. Hypertrophic scars and keloids are the results of a series of cellular and molecular changes which their identification can guide us toward new treatment modalities which may decrease the pathological factors, or help balancing the repair mechanism; thus inhibiting extensive scar formation. In this article, we have reviewed the latest treatment methods, as well as molecular and cellular reactions, which lead to the formation of hypertrophic scars and keloids.