In contrast to women, fertility in men persists until a very old age. However, testicular function of both the exo- and endocrine compartments decreases in old age, causing a series of clinical symptoms which are analogous to, although less pronounced than, the menopausal syndrome. These symptoms can be considered to represent the male climacterium or andropause. However, whereas at menopause ovarian hormonal secretion ceases almost completely, the decrease in the levels of biologically active endrogens (free testosterone) is only moderate and many elderly men have free androgen levels that would be considered normal for young men. Moreover, whereas many well-controlled studies have shown the benefit of hormonal replacement therapy, at least for symptomatic posmenopausal women, so far no well-controlled studies exist that prove a favourable risk/benefit balance of androgen substitution in elderly men. The major risk is the potentially stimulating effect of androgens in elderly men who frequently present with subclinical prostatic carcinoma. Therefore, the generalized use of androgen substitution in elderly men cannot, as yet, be recommended.