Although the incidence of breast cancer in Asia remains lower than in North America, Western Europe,and Oceania, rates have been increasing rapidly during the past few decades, and Asian countries now accountfor 40% of breast cancer cases diagnosed worldwide. Breast cancer mortality has also increased among Asianwomen, in contrast to decreased mortality in Northern America, Western Europe, and Oceania. These increasedrates are associated with higher prevalence of breast cancer risk factors (e.g., reduced parity, delayed childbirth,increased obesity) that have accompanied economic development throughout the region. However, Asian regions(western, south-central, south-eastern, and eastern) and countries differ in the types and magnitude of changesin breast cancer risk factors, and cannot be viewed as a single homogeneous group. The objective of this paperwas to contrast the heterogeneous epidemiology of breast cancer by Asian regions and countries, and to suggestpotential avenues for future research.