Major League Soccer (MLS) is a men's professional soccer league sanctioned by the United States Soccer Federation, which represents the sport's highest level in the United States. The league comprises 29 teams—26 in the United States and 3 in Canada—since the 2023 season. MLS is headquartered in Midtown Manhattan.

Soccer-specific stadium is a term used mainly in the United States and Canada to refer to a sports stadium either purpose-built or fundamentally redesigned for soccer and whose primary function is to host soccer matches, as opposed to a multi-purpose stadium which is for a variety of sports. A soccer-specific stadium may host other sporting events and concerts, but the design and purpose of a soccer-specific stadium is primarily for soccer. Some facilities have a permanent stage at one end of the stadium used for staging concerts.