AbstractThe Chemical Weapons Convention is a science-based international treaty for the disarmament and non-proliferation of chemical weapons. The Organisation for the Prohibition of Chemical Weapons (OPCW) serves as its implementing body. The treaty bans chemicals weapons, includes a verification mechanism to monitor compliance, and requires scientific and technical expertise for effective implementation. This necessitates a continuous engagement with scientific communities, whether informal or institutionalized (as demonstrated by the Designated Laboratories, Validation Group, and Scientific Advisory Board (SAB), of the OPCW), to ensure operation of the treaty keeps pace with scientific advances, and that enabling opportunities to meet challenges through scientific advances can be seized. The effective use of science for treaty implementation demands scientific literacy for decision making. Herein, the Convention, its scientific basis, need for scientific expertise, and mechanisms through which the OPCW engages scientists, are described. The function of the OPCW SAB, its review of science and technology to advise disarmament and non-proliferation policymakers, and its role in raising awareness of science within the world of international diplomacy, are reviewed.