Two decades have passed since the concept of Maximal Androgen Blockade (MAB) was first applied to the clinical treatment of prostate cancer. The theory is that by cutting off the supply of androgen from the adrenal gland, androgen blockade of the prostate could be made more complete. However, to date the clinical benefit of MAB has failed to live up to the theoretically expected effect. Having said that, fundamental research and clinical trials in recent years do indicate that the benefit of MAB is not merely an illusion.