The role of science in international climate policy is coming under increasing pressure. The Intergovernmental Panel on Climate Change (IPCC), the central liaison body between politics and science, is threatened with a loss of importance and influence. The plenary session, which will take place from Feb. 24 to 28 in Hangzhou, China, is the last chance to adopt a timetable that will enable the IPCC to continue to provide political decision-makers with relevant information in good time.