In this article, Harold Jacobson and Edith Brown Weiss explain how the Council`s Committee for Research on Global Environmental Change holds a leading position in research on countries` implementation of and compliance with international environmental agreements. Jacobson and Brown Weiss lay out how the group defined implementation and compliance and ask several questions that are now relevant to broader agreements on climate change. While the project focused on what countries do when they are signatories to an agreement, not what happens when they withdraw – as the Trump administration did with the Paris Agreement – understanding how the state behaves on this and how sociologists did it more than 20 years ago remains valuable. UN Security Council Resolution 1540 sets out the obligations of all UN Member States to impose or purchase by non-State actors effective measures against chemical, nuclear or biological weapons, their means of delivery or related materials. These include measures to prevent the proliferation of chemical, nuclear or biological weapons. .