Since it was founded in 1918, the American National Standards Institute (ANSI) has coordinated the development of voluntary consensus standards in the United States and has represented the needs and views of U.S. stakeholders in standardization forums around the globe. ANSI is the U.S. member body to ISO and, via its U.S. National Committee, the International Electrotechnical Commission (IEC). ANSI is also a member of the International Accreditation Forum (IAF).

ANSI does not write standards; rather, the Institute accredits standards developers that will establish consensus among qualified groups. Its guiding principles " consensus, due process and openness " are followed by the 220 distinct entities currently accredited to develop and maintain nearly 10 000 American National Standards (ANS). Though all ANS are developed as voluntary documents, U.S. federal, state, or local bodies are increasingly referring to ANS for regulatory or procurement purposes. Many ANS are also national adoptions of globally relevant international standards.

The Institute's membership is comprised of a broad range of businesses and industrial organizations, standards setting and conformity assessment bodies, trade associations, labor unions, professional societies, consumer groups, academia, and government organizations for the purpose of enhancing global business competitiveness and improving the quality of life for the world's citizens.
The interests of more than 125000 companies and 3,5 million professionals are represented through ANSI's headquarters in Washington, DC, and its operations office in New York City.