Outside of the Olympics, the IAAF World Championships are the most prestigious event for elite marathoners and track athletes. They're held every two years, and the 2017 version will take place August 4-13 in London.
Who will run the marathon for the U.S. at the world championships? The selection procedure is different than it is for the Olympics, when runners enter the marathon trials and top three finishers that day make the team. Instead, they are ranked according to their marathon times between January 1, 2016, and April 24, 2017, and then the fastest runners earn invitations.