"The Gang F**ks Up Abbott Elementary" is the first episode in the seventeenth season of It's Always Sunny in Philadelphia, and the 171st overall.
The first half of the crossover premiered as the ninth episode of season four of Abbott Elementary, titled "Volunteers. The Sunny half of the crossover, filmed entirely on Abbott's sets and shot in the style of a typical episode, was written by Rob McElhenney, Charlie Day, and Keyonna Taylor, and directed by Todd Biermann. According to Abbott's Patrick Schumacker, the first episode of Season 17's production order was the crossover episode, which they had to start production on "a little early" so that it could play off of the Abbott episode.