The recent crystallization of the estradiol and raloxifene ER complex 19 has provided fascinating clues to the mechanism of action of antiestrogens and confirmed, for the first time, a mechanism of drug resistance for tamoxifen. The new strategy to prevent breast cancer as a beneficial side effect of the prevention of osteoporosis 7.11 is poised to revolutionize health care for postmenopausal women. The convergence of molecular biology and medicine has the potential to open up new therapeutic opportunities for the discovery of novel targeted antiestrogens to either the ERα or the newly discovered ERβ. There is currently intense interest in describing the distribution of ERα and ERβ throughout the female and male organ systems. As a direct result of this research new targeted drugs hold the promise for the specific control of diseases not only in women but also in men.