The United States Swimming National Championships (a.k.a. "Nationals") are held annually, typically in early August. The event is organized by USA Swimming, and is held in a long course (50m) pool. In the past, and as recently as 2007, there were 2 meets annually: and Spring and Summer Nationals. The Spring meet began as a 25-yard (short course) meet, while the Summer meet was long course. Prior to USA Swimming's creation in the late 1970s, the meet was run by the AAU.
Phillips 66 began sponsoring the meet in 1973, which continues through today although the branding of the sponsorship changed to ConocoPhillips in the early 2000s. This is one of the longest sponsorships in U.S. sports.