Advertising Standards Authority (United Kingdom)

The Advertising Standards Authority (ASA) is the self-regulatory organisation of the advertising industry in the United Kingdom. The ASA is a non-statutory organisation and so cannot interpret or enforce legislation. However, its code of advertising practice broadly reflects legislation in many instances. The ASA is not funded by the British government, but by a levy on the advertising industry.

Its role is to "regulate the content of advertisements, sales promotions and direct marketing in the UK" by investigating "complaints made about ads, sales promotions or direct marketing", and deciding whether such advertising complies with its advertising standards codes. These codes stipulate that "before distributing or submitting a marketing communication for publication, marketers must hold documentary evidence to prove all claims, whether direct or implied, that are capable of objective substantiation" and that "no marketing communication should mislead, or be likely to mislead, by inaccuracy, ambiguity, exaggeration, omission or otherwise". The agency has also restricted ads featuring scantily clad women.

Guy Parker has been chief executive of the ASA since June 2009.