Most proposals for new international agreements aim to address important global challenges. If the goal is to solve problems, then the value of these agreements depends on their ability to influence the world — to shape norms, constrain behavior, facilitate cooperation, and mobilize action. A recent review of empirical studies has suggested that many international agreements fail to achieve their aspirations. The review indicates that the form in which states make commitments to each other — through an international legal agreement or through other means — may not be as important as commonly thought. It is the content of the commitments and how these are supported by mechanisms to encourage implementation that matter the most. When developing proposals for new international agreements, like the one that has recently been proposed to address antibiotic resistance (ABR), attention to implementation mechanisms should therefore be equal to if not greater than the attention paid to its form.