Bulked segregant analysis, a technique used in genetics

Boy Scouts of America

Birmingham Small Arms Company, a British manufacturer of military equipment and vehicles including motorcycles

Bethesda Softworks Archive, a common extension used by this company for the data needed by its games

British Soap Awards

BPO Services Association Unlimited (BSA/U)

Business Software Alliance

Bank Secrecy Act

Baltimore School for the Arts

Brazilian Space Agency

Body surface area

British School at Athens

British Stratego Association

Bovine serum albumin

British Sociological Association

Building Societies Association

Bronze Service Arrowhead

Broadcasting Standards Authority