Anastrozole is a third-generation aromatase inhibitor with an extensive evidence base to preferentially support its use in multiple scenarios in endocrine-responsive breast cancer. These include neoadjuvant treatment, immediate and delayed adjuvant treatment, salvage treatment and first-line treatment of advanced breast cancer. Compared to tamoxifen, it offers superior efficacy and a different side effect profile that results in better tolerance and compliance. Anastrozole is considered cost effective compared with tamoxifen in a variety of healthcare systems. Anastrozole has been applied to the management of a number of endocrine conditions other than breast cancer. The major future areas of interest are in breast cancer prevention, integration with surgery, radiotherapy and other systemic targeted therapies.