As stipulated in Article 31 of the National Defense Act, the Ministry of National Defense (MND) shall “within ten months after each presidential inauguration, publicly submit the Quadrennial Defense Review to the Legislative Yuan.” This is the fifth edition of the Quadrennial Defense Review (QDR) since 2009. The focus of this QDR is to embody the President’s defense concept; his “four pillars of peace initiative” for defense, economy, diplomacy, and cross-Strait relations; and reveal highlights of future defense reforms, aiming to allow both the people and the international community to know our national defense and military strategies as well as our important policy plans.