Résumé : This article reflects on progress made in recent years with respect to bench-to-bedside research in breast cancer. It shows how the advent of molecular oncology-accompanied by high-throughput experimental methods and "omics" technologies-has led researchers to realize that breast cancer is a heterogeneous disease for which a "one size fits all" approach to patient treatment is no longer optimal. This, in turn, has contributed to a change in thinking about clinical trial design. Using several examples of clinical trials being run under the umbrella of the Breast International Group, including the recently launched Microarray In Node-negative Disease may Avoid ChemoTherapy study and Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization study, the article looks at how translational research and biological specimen collection has become a central component of clinical research design in a relatively short period of time. This, plus an evolution in research culture that has resulted in increased international collaboration among research networks, groups, and centers, will arm researchers with the tools needed to develop truly individualized cancer treatments for patients in the future.