The treatment of adolescent males with hypogonadism using testosterone is dependent on the underlying diagnosis as well as the patient's and family's preferences. Those with testicular failure, always a pathologic condition, begin lifelong therapy, while short-term therapy is often begun for those who have a delayed puberty. There is a wide variety of testosterone formulations available, with differences in adverse events sometimes associated with the method of administration. The goals of treatment involve stimulating physical puberty, including achievement of virilization, a normal muscle mass and bone mineral density for age, and improvement in psychosocial wellbeing. While androgen therapy results in physical changes of puberty, the potential for fertility must be considered for those with permanent gonadotropin deficiency. in this population, therapy with gonadotropins or gonadotropin releasing hormone may be effective. For those with testicular failure, fertility may be possible but requires assisted reproductive procedures.