The American Bar Association (ABA) is a voluntary bar association of lawyers and law students; it is not specific to any jurisdiction in the United States. Founded in 1878, the ABA's stated activities are the setting of academic standards for law schools, and the formulation of model ethical codes related to the legal profession. As of fiscal year 2017, the ABA had 194,000 dues-paying members, constituting approximately 14.4% of American attorneys. In 1979, half of all lawyers in the U.S. were members of the ABA. The organization's national headquarters are in Chicago, Illinois, and it also maintains a significant branch office in Washington, D.C.

A bar association is a professional association of lawyers as generally organized in countries following the Anglo-American types of jurisprudence. The word bar is derived from the old English/European custom of using a physical railing to separate the area in which court business is done from the viewing area for the general public.