Why have Europe and the United States failed to reach agreement on global climate change policy? Professor Wiener will offer perspectives drawn from his sixteen years of experience as an academic expert and a participant in the climate treaty negotiations. He will examine the role of important institutional factors, in particular: (1) the national net benefits to participation perceived by each government, and indeed the use of a benefit-cost framework for analyzing such perceived national net benefits; (2) the design of the climate treaties, including their scope (coverage of gases, sectors and sinks), and their use of economic incentive instruments, as key factors in national net benefits; (3) ideology or national culture regarding climate, "precaution" and the environment; and (4) domestic political institutions. Professor Wiener will argue that the discord is not surprising when viewed from these institutional perspectives. He will discuss options for future progress, in a world of not only the US as the largest emitter, but also an enlarging European Union and the growing power of China.