Longtermism is a moral philosophy that is increasingly gaining traction around the United Nations and in foreign policy circles. Put simply, Longtermism holds the key premise that positively influencing the long-term future is a key moral priority of our time. The foreign policy community in general and the the United Nations in particular are beginning to embrace longtermism.  Next year at the opening of the UN General Assembly in September 2023, the Secretary General is hosting what he is calling a Summit of the Future to bring these ideas to the center of debate at the United Nations. Will MackAskill is Associate Professor of Philosophy at the University of Oxford. He is the author of the new book "What We Owe the Future" which explains the premise and implications of Longtermism including for the foreign policy community, particularly as it relates to mitigating catastrophic risks to humanity.