| Amateur Baseball Umpire Association: An umpire information center. Umpire associations, umpire equipment, umpire rules; a resource center for umpires to find and share information. |
| American Amateur Baseball Congress: Coordinates play among US leagues in seven age brackets, from sub-teens through adults. Includes rules, tournament dates, and list of regions and age divisions. |
| American Baseball Coaches Association (ABCA): A nonprofit organization having more than 5,000 members, including coaches from every state in the country and over 200 international members. |
| American Federation of Umpires(AFU): Group of baseball and softball umpires who share the common goal of consistent improvement in their officiating skills and knowledge of the game. Features clinics, a newsletter, and various resources. |
| Major League Baseball Players Alumni Association: Organization of former players. Features information, history, and news of the organization's activities. |
| The United States Amateur Baseball Association.: The USABA is here for the promotion and development of the players and fans in youth baseball pastseason tournament competitions at state, regional, and national level. |