John Podesta draws lessons from pollutant reduction negotiations to the current coronavirus pandemic. By 2013, hydrofluorocarbons, pollutants more potent than carbon dioxide, had become an international problem for dealing with climate change. Podesta, a former White House Chief of Staff, helped steer the Obama administration’s efforts to coordinate with China—first from outside the administration and then as counselor to the president. Washington and Beijing agreed to wind down the production of HFCs and persuade other countries to join them to combat climate change.