The G20 summit in Hangzhou will be the first meeting of leaders from the world’s largest economies since the Paris Agreement on climate change was announced in December 2015. This agreement, adopted by 195 states, represents unprecedented global solidarity and commitment to action. Despite the numerous political and economic disruptions the world has seen over the past year, many countries are already taking steps to ratify the agreement as soon as possible. As host of the Hangzhou Summit, China deserves particular recognition for its leadership in implementing the Paris Agreement through long-term domestic policies and for having such a strong, bold focus on sustainable growth in its 13th Five-Year Plan. In China, swift action is already engaging businesses and investors in helping to grow the country’s low-carbon economy. It represents a compelling example for others to follow. Delivering the Paris ambition to limit global temperature increase to below 1.5 degrees Celsius above pre-industrial levels requires economic, political and social change unlike anything before. It can only be addressed with the leadership and commitment of the G20 members, with the support of their largest cities.