The argument to include NGS in clinical decision making is based on several concepts including: 1) Actionable mutations are well described in the literature and targeted therapies are now available in the approved or trial setting; 2) Mutations might provide predictive capabilities for certain types of standard and experimental therapies and, therefore, offer an enrichment strategy in designing clinical trials; and 3) Mutations might offer prognostic and/or predictive information in certain types of breast cancer, such as HER2+ and triple negative breast cancer. The gene discussed is ERBB2; the disease is breast cancer.