The only indication for testosterone administration in older men is testosterone replacement therapy for male hypogonadism. Compared with young hypogonadal men, the diagnosis and management of male hypogonadism in older men is more challenging. Both the clinical manifestations of androgen deficiency and low testosterone levels may be caused or modified by comorbid illnesses that occur and medications taken more frequently by older men, resulting in a greater likelihood for overdiagnosis of hypogonadism and subsequent inappropriate use of and inadequate response to testosterone treatment. It is important to use a systematic, holistic approach to the diagnosis and management of older men with hypogonadism.