D.C. United is an American professional soccer club based in Washington, D.C. The club competes in Major League Soccer (MLS) as a member of the Eastern Conference. Domestically, the club has won four MLS Cups (league championships), four Supporters' Shields (league regular season), three U.S. Open Cups (domestic cups), and six Eastern Conference championships. In international competitions, the club has one CONCACAF Champions Cup title and one Copa Interamericana, the only United States team to win the latter. In terms of trophies won, it is the joint-most successful overall club in American soccer (tied with the LA Galaxy).

Founded in 1994, the club was an inaugural franchise in Major League Soccer, playing in the league since its first season in 1996. The club played a majority of its matches at Robert F. Kennedy Memorial Stadium from 1996 until 2017 before moving to the soccer-specific stadium, Audi Field, in 2018, where it has played since. D.C. United was one of the premier franchises in Major League Soccer, and in American soccer in the late 1990s, where it won the bulk of its trophies. Players such as Raúl Díaz Arce, Marco Etcheverry, Roy Lassiter, Jaime Moreno, Ben Olsen, and Eddie Pope, along with head coach, Bruce Arena, helped the club win eight of their 12 major titles from 1996 through 2000. The club would win an MLS Cup, a U.S. Open Cup, and two Supporters' Shield titles under Piotr Nowak and Tom Soehn in the mid-to-late 2000s. In 2013, under the management of Ben Olsen, the club won the U.S. Open Cup, its most recent major trophy.

Throughout the 2010s, and into the early 2020s, the club managed by Ben Olsen, went through mediocrity, with only one major trophy, and several missed playoff appearances, including two last place finishes in the league. During this time, some high-profile acquisitions joined United, including Wayne Rooney, and several homegrown players began making impacts on the United squad including Bill Hamid, Andy Najar, and Kevin Paredes. After a string of poor seasons, Olsen was fired in 2020, after a ten-year tenure as head coach. Olsen was replaced by Hernán Losada, who managed the club until 2022, when he was replaced by former player Wayne Rooney. Rooney was fired in October 2023 after a poor managerial effort, and was replaced in January 2024 with former New York Red Bulls manager Troy Lesesne who manages the club as of May 2024.