Hypogonadism is a clinical syndrome that results in hormone deficiency in men and women. Primary hypogonadism is caused by gonadal (testicular or ovarian) failure. Secondary hypogonadism is the result of a dysfunction within the hypothalamus and/or pituitary. Diagnosis of hypogonadism requires a comprehensive health history, evaluation of the signs and symptoms, complete physical examination, as well as laboratory and diagnostic testing for both sexes. Hormone replacement is the hallmark of hypogonadism treatment. Restoring and/or maintaining quality of life is a major consideration in the management of patients with hypogonadism.