A common perception among international relations policymakers and theorists is that states’ primarily self-serving motivations inhibit their participation in promoting international distributive-fairness considerations. This article asserts that this notion is significantly incomplete and misleading; it results in deficient theories and, more importantly, in sub-optimal international arrangements. The deficiency of current approaches is that they view distributive fairness as only performing a normative wealth redistribution function and fail to recognize its practical insurance function. In a very crude way, “distributive fairness” means that countries should pay for the provision of international public goods (for example, controlling global warming by reducing emissions) according to their relative economic abilities. In the short-term, this means that rich developed countries should pay more than poor developing ones. However, in long-term agreements where there are considerable uncertainties with respect to which countries will be wealthier in the future, it is also a partial insurance against becoming poor(er). Therefore, incorporating fairness considerations into international agreements insures many, if not all, countries against “overpaying” as compared to what other countries are required to pay. Once policymakers recognize this insurance function, they can facilitate more effective international agreements that encourage countries to undertake more substantial obligations. This will help policymakers to better coordinate states’ actions in order to meet the growing demand for many crucially undersupplied global public goods.