The Amateur Athletic Union (AAU) of the United States, Inc. is a multi-sport 501(c)3 tax-exempt not for profit national organization. Softball/Baseball organizations such as Nations Baseball, Top Gun, Triple Crown, USSSA, or any others, are separate and distinct entities from the AAU. To participate in any AAU-sanctioned event, all players and coaches must be members of the AAU. To obtain membership in AAU, go to www.aausports.org and click on Join AAU.

Note that one of the benefits of becoming an AAU member is the sport accident and general liability insurance coverages provided. The basic AAU membership includes coverage while participating in AAU-sanctioned events; the AAU extended coverage (AB-Added Benefit) membership includes coverage for both AAU-sanctioned events and sanctioned events that are not related to the AAU.