This paper explains why the approach taken so far to mitigate global climate change has failed. The central reason is an inability to enforce targets and timetables. Current proposals recommending even stricter emission limits will not help unless they are able to address the enforcement deficit. Trade restrictions are one means for doing so, but trade restrictions pose new problems, particularly if they are applied to enforce economy-wide emission limitation agreements. This paper sketches a different approach that unpacks the climate problem, addressing different gases and sectors using different instruments. It also explains how a failure to address the climate problem fundamentally will only create incentives for different kinds of responses, posing different challenges for climate change governance.