As a quintessential long-term policy problem, climate change poses two major challenges. The first is to develop, under considerable uncertainty, a plan for allocating resources over time to achieve an effective policy response. The second is to implement this plan, once arrived at, consistently over time. We consider the second of these two challenges, arguing that it consists of three interrelated, commitment problems—the time inconsistency problem, the domestic politics problem, and the anarchy problem. We discuss each of these commitment problems in some detail, explore how they relate to climate policy, and suggest institutional designs that may help limit their adverse impact. While each of these commitment problems is difficult to tackle on its own, climate change requires us to cope with all of them at once. This is likely one major reason why we have so far made only modest headway on this vital issue.

In international regimes research, one of the most important questions is how effective regimes are in delivering what they were established and designed to achieve. Perhaps the most explicit and rigorous formula for measuring regime effectiveness is the so-called Oslo-Potsdam solution. This formula has recently been criticized by Oran Young, himself one of the founding fathers of regime analysis. The present article reviews and responds to his critique and provides several extensions of the Oslo-Potsdam solution. Our response may be summarized in three points. First, we recognize that difficult problems remain unsolved. Second, we argue that for some of the most profound problems there is no escape; we need to engage in counterfactual reasoning, and we need some notion of the “best” solution achievable (such as the “collective optimum”). Finally, we would welcome efforts to further develop and refine the Oslo-Potsdam formula as well as alternative approaches.