IAB

IAB may refer to:

Organisations

 * Institute of Architects Bangladesh, a professional organisation for architects in Bangladesh
 * Interactive Advertising Bureau, for the online advertising industry
 * Internal Affairs Bureau, part of the New York City Police Department, US
 * International Agrarian Bureau or Green International, based in Prague, Czech Republic
 * Institute of Accountants and Bookkeepers, UK
 * International Association of Bryologists, promoting bryology (the study of mosses, liverworts, and hornworts)
 * Internet Advertising Bureau, a UK trade association
 * Internet Architecture Board, a committee of the Internet Engineering Task Force (IETF)
 * Israel Association of Baseball, to promote and develop baseball in Israel

Air force bases

 * Isa Air Base, Bahrain
 * McConnell Air Force Base (IATA airport code), Wichita, Kansas, US

Science and technology

 * IAB meteorite, a group of iron meteorites
 * Individual Address Block, in computer networking

Other uses

 * International Accounting Bulletin, a UK accountancy publication