Why did states agree that the global fight against drug trafficking should be led by an international organization vested with an independent legal personality, a considerable budget, and powerful direct and indirect enforcement tools, but fail to adopt a similarly far-reaching form of institutionalized cooperation to combat illicit transfers in small arms and light weapons? This question is striking, because the trafficking of narcotic drugs and of small arms and light weapons seem – at first glance – to be very similar public policy problems: both kill and ruin the health of a comparable number of people; both provide a playground for profit-seeking criminals as well as ideologically motivated rebels and terrorists; and both require the coordinated response of a large number of producer, transhipment, and consumer countries. To rephrase the opening question in more general terms: Why do states adopt strikingly different designs for international institutions created to tackle seemingly similar problems? This puzzle is at the heart of this study's theoretical inquiry.

While the academic discussion of the reasons why independent states create institutions to facilitate international cooperation has started to reach its point of saturation, the more fine-grained inquiry into the factors explaining the pronounced variance in the design of these institutions is still in its infancy. So far, not even a common language has been developed to describe the most salient dimensions along which institutional designs vary.