The character of contemporary international relations is far more complex than that confronted by the architects of the UN in 1945. Problems are interlinked to an extent previously unimagined by those designers, but the organizations they helped create were charged with solving problems as they were defined at the time of the founding. The UN was designed to cope with problems of the recent past that the architects felt could be treated as if they were discrete: collective security was designed to avoid the presumed military causes of World War II; balance-of-payments stability was pursued to prevent the competitive devaluations of the Great Depression. The current agenda now includes issues that were not imagined at San Francisco, including macroeconomic management, sustainable development, ecological disaster avoidance, and nuclear proliferation. The new problems reflected by these issues exist, to a large extent, by virtue of the successful reduction of barriers to trade and improved individual “quality of life” that the UN system helped to develop. Moreover, virtually all of the original concerns apparent at San Francisco—collective security, stable world commodity markets, public health, expanding trade, and stable currencies—remain with us.