The application of high-throughput techniques to profile DNA, RNA, and protein in breast cancer samples from hundreds of patients has profoundly increased our knowledge of the disease. The etiologic events that drive breast cancer are finally coming into focus and should be used to set priorities for clinical trials. In this Prospective, we summarize some of the headline conclusions from 6 recent breast cancer "omics profiling" articles in Nature, with an emphasis on the implications for systemic therapy.