Global leaders will gather at the United Nations on September 18 as the debate session of the world body's General Assembly officially begins.
Much of the attention will be on U.S. President Donald Trump, who will make his debut at the 193-member UN with a speech on September 19. French President Emmanuel Macron is also scheduled to make his first appearance as a national leader.
Among those not scheduled to attend are Russian President Vladimir Putin, who has only made rare visits to the UN, and German Chancellor Angela Merkel. Both are sending their foreign ministers.
The event will also mark the debut of the new UN chief, Antonio Guterres, the former Portuguese prime minister who will preside over the Assembly's general debate, which runs through September 25.
The leaders will attempt to focus on several world flash points, with North Korea’s continued defiance of the UN ban on its nuclear and ballistic-missile programs likely to be issue No. 1.
The UN Security Council and nearly all nations individually have condemned Pyongyang’s missile tests, the latest of which came on September 15 when North Korea fired a ballistic projectile that flew over Japan.
The Council called the launch "highly provocative" and an "outrageous action."
Still, not all nations are in agreement about how far the world body should go with enhanced sanctions against Pyongyang -- China and Russia have rejected a U.S. call to take more "direct actions" to deter the North.
Pyongyang will be sending a low-level representative to the Assembly.
Also facing the world leaders is a humanitarian crisis involving some 400,000 Rohingya Muslim refugees who have fled violence in Burma and are languishing in camps in Bangladesh.
Terrorism and global warming -- and U.S. intentions in regard to the Paris climate accords -- are also likely to be the subject of intense discussion, and disagreement, among world leaders.
In the past, Trump has been a vocal critic of the UN, and aides say he will be pushing "U.N. reform" -- mainly looking for members to contribute more to global projects, including peacekeeping operations, which cost some $8 billion a year.
Jon B. Alterman, a senior vice president at the Center for Strategic and International Studies in Washington, told The New York Times that “the world is still trying to take the measure of this president.”
“For a number of leaders, this is going to be their first chance to see him, to judge him, to try to get on his good side,” he said.