Reductions of methane, black carbon and tropospheric ozone could halve warming during the 2030s, while a fairly aggressive strategy to reduce carbon dioxide would do little over the next 20–30 years. Concerning methane, governments must act quickly to take advantage of this opportunity. Production of ‘unconventional’ natural gas, such as shale gas, has increased significantly and with conventional sources could meet current consumption levels for over 240 years. However, the benefit of methane as a transitional fuel from coal to renewables is questionable due to methane leakage during production. Also, rising temperatures are releasing methane from melting permafrost, but governments are not required to report these emissions. Thus, countries are farther from meeting their targets and the global community is farther from reaching the goal of limiting warming to 2°C above pre-industrial levels than emissions data suggest. This article establishes an agenda for fuller accounting of methane in the climate change regime.