There is much debate about the risks and benefits of tamoxifen, most specifically about the incidence of associated endometrial cancer. Nearly all of the published trials on the subject have been criticized for methodological flaws and various forms of bias, making resolution of this controversy difficult. There is a consensus, however, that tamoxifen results in an increased incidence of both premalignant and malignant lesions of the endometrium. As the indications for tamoxifen continue to broaden, a larger number of women will be subjected to the potential adverse effects of tamoxifen. Many techniques for screening patients on tamoxifen for the development of endometrial abnormalities have been suggested. None of these methods appears to be consistently clinically or cost effective. We have reviewed the literature on endometrial surveillance in tamoxifen treated women with a focus on the larger publications reported within the past year. From this, we have provided what we hope to be safe and cost-effective recommendations for the management of these patients.