This article draws upon more than 15 years of 'participant-observation' with international efforts to regulate the global trade in small arms and light weapons to examine: the overall trajectory, major successes, and shortcomings of inteniational efforts to deal with the negative consequences of the proliferation and misuse of small arms and light weapons; and the role, scope, and impact of expert knowledge and policy-relevant research in shaping 'global public policy'. By focusing on the specific role and experience of the Small Arms Survey project, a research-based NGO that played a high-profile role in these efforts, it outlines the general conditions that shape the prospects for academic research and analysis to influence global public policy both through agenda setting and framing, and through highlighting policy solutions. It also underscores the constraints upon the uptake of policy-relevant research, including epistemic uncertainty and governmental receptiveness. It concludes with some observations on the overall role of expert knowledge in the shaping of global public policy. and on he trajectory of international efforts to tackle small arms proliferation and misuse.