Level of minor league baseball two steps away from the major leagues. Players are promoted from A Advanced to AA, and from AA to AAA ball. The three leagues that make up AA ball are the Southern League, Texas League, and Eastern League.

In the early to mid-'00s, AA became the primary level for development and refinement of major-league talent, as AAA ball became a taxi squad of sorts for the big club. Players at this level usually have the physical skills to advance to the bigs; hot prospects will often be promoted straight to the majors from this level.