ASA, as an abbreviation or initialism, stands for:
U.S. organizations
Acoustical Society of America
African Studies Association
Alpha Sigma Alpha (???), U.S. national sorority
American Sailing Association
American Scientific Affiliation, an organization of Christians in science
American Seniors Association
American Society of Agronomy
American Society of Anesthesiologists
American Sociological Association
American Standards Association, former name of the American National Standards Institute
American Statistical Association
American Stroke Association or American Heart Association
Americans for Safe Access, marijuana law reform group
Autism Society of America
Associate of the Society of Actuaries
Non-U.S. organizations
Advertising Standards Authority, British regulator of the advertising industry
Albany Students' Association, at Massey University's Albany Campus in Auckland, New Zealand
Astronomical Society of Australia, the professional society of astronomers
Source:
http://en.wikipedia.org/wiki/Asa