[en] Commission (CNSC) mission is independent evaluation of licensees submittals in support of their safety cases. Reactor physics analysis, criticality safety, fuel and material science are among the core competencies essential to the pursuit of the CNSC mission. Although the licensees have the responsibility for safety and supporting technical analyses, the licensees and, indeed, the public expect the regulator to have capabilities in these areas that are at or very near the state-of-the-art and to use objective evidence, including advanced computational methods and accurate experimental evidence. Therefore, CNSC has enhanced over the last two decades its technical capabilities in these areas to make technically sound regulatory recommendations.