The following is a timeline of the organizational changes in the National Basketball Association (NBA), including contractions, expansions, relocations, and divisional realignment. The league was formed as the Basketball Association of America (BAA) in 1946 and took its current name in 1949. The histories of NBA franchises that were also members of the American Basketball League (ABL), National Basketball League (NBL), National Pro Basketball League (NPBL), and American Basketball Association (ABA) are also included.