Androgen replacement therapy (ART) is usually lifo-long, and should only be started after androgen deficiency has been proven by hormone assays. The therapeutic goal is to maintain physiological testosterone levels. Testosterone rather than synthetic androgens should be used. Oral 17 alpha-alkylated androgens are hepatotoxic and should not be used for ART. There is no indication for androgen therapy in male infertility. Although androgen deficiency Is an uncommon cause of erectile dysfunction, all men presenting with erectile dysfunction should be evaluated for androgen deficiency. If androgen deficiency is confirmed, investigation for the underlying pathological cause is required. Contraindications to androgen therapy are prostate and breast cancer. Precautions include using lower starling doses for older men and induction of puberty. Intramuscular injections should be avoided in men with bleeding disorders. Androgen-sensitive epilepsy, migraine, sloop apnoea, polycythaemia or fluid overload need to be considered. Competitive athletes should be warned about the risks of disqualification. ART should be initiated with Intramuscular Injections of testosterone esters, 250 mg twice weekly. Maintenance requires tailoring treatment modality to thf: patient's convenience. Modalities currently available include testosterone Injections, Implants, or capsules. Choice depends on convenience, cost, availability and familiarity. There is no convincing evidence that, in the absence of proven androgen deficiency, androgen therapy is effective and safe for older men per se, In men with chronic non-gonadal disease, or For treatment of nonspecific symptoms. Until further evidence Is available, such treatment cannot be recommended.