Dr. Symmans’ defining contributions to the field of breast cancer include an improved method to measure pathologic response, and the development of genomic assays to predict both response and survival following neoadjuvant chemotherapy. Within 5 years of initial publication, the residual cancer burden (RCB) method of pathologic evaluation has become a standard secondary or primary response endpoint in clinical trials (e.g. the online RCB calculator website had 17,000 visits in 2011). RCB has also formed a basis for training more effective chemopredictive genomic assays that consider primary resistance separately from excellent response, and for understanding the sequential synergy that can be achieved with chemo-endocrine therapy for Stage II-III breast cancer. These findings are re-shaping the approach to development of “omics-based” predictive tests. In parallel, he has advanced the practical application of minimally invasive breast biopsy techniques for translational research through evidence-based studies of biospecimen yield and quality.