Endometriotic lesions are associated with hormonal imbalance, including increased estrogen synthesis, metabolism and progesterone resistance. These hormonal changes cause increased proliferation, inflammation, pain and infertility. Hormonal imbalances are targets for treatment. Therapeutic strategies and innovations of hormonal drugs for endometriosis are increasing. Acting on estrogen receptors are hormonal drugs decreasing systemic and local estrogen synthesis (GnRH analogs, GnRH antagonists, Aromatase inhibitors) or estrogen activity (selective estrogen receptor modulators). The progesterone resistance is counteracted by progestins (Medroxyprogesterone acetate, Dienogest, Danazol, Levonorgestrel) or by Selective progesterone receptor modulators, a class of drugs under development. The future trend will be to define new drugs to use for prolonged period of time and with poor side effects considering endometriosis a chronic disease.