Recently, the guidelines for adjuvant hormonal therapy for primary breast cancer were presented at the National Institute of Health Consensus Development Conference in November 2000 and at the 7th International Conference on Adjuvant Therapy of Primary Breast Cancer in February 2001. Adjuvant hormonal therapy should be offered basically to all patients with tumors expressing estrogen receptor (ER) and/or progesterone receptor (PR), assessed by immunohistochemistry. The consensus statements recommended 5 years of tamoxifen as standard hormonal therapy for both premenopausal and postmenopausal patients with ER and/or PR positive tumors. Ovarian ablation or suppression of ovarian function combined with tamoxifen is a treatment of choice for premenopausal patients with high-risk endocrine-responsive tumors. The selection of hormonal therapies and their combination with chemotherapy should be decided according to the assessment of risk of relapse, side effects, and patients' condition and preference.