Climate change is the defining issue of our time and now is the defining moment to do something about it. There is still time to tackle climate change, but it will require an unprecedented effort from all sectors of society. To boost ambition and accelerate actions to implement the Paris Agreement on Climate Change, UN Secretary-General António Guterres is asking leaders, from government, business and civil society, to come to the 2019 Climate Action Summit on 23 September with plans to address the global climate emergency. The Summit will spark the transformation that is urgently needed and propel action that will benefit everyone.