AOAC International is a 501(c) non-profit scientific association with headquarters in Rockville, Maryland. It was founded in 1884 as the Association of Official Agricultural Chemists (AOAC) and became AOAC International in 1991. It publishes standardized, chemical analysis methods designed to increase confidence in the results of chemical and microbiological analyses. Government agencies and civil organizations often require that laboratories use official AOAC methods. AOAC is headquartered in Rockville, Maryland, and has approximately 3,000 members based in over 90 countries.