American Library Association (ALA)
http://www.ala.org/
American Society for Information Science and Technology (ASIST)
http://www.asis.org/
American Society of Indexers (ASI)
http://www.asindexing.org/site/
Australian Society of Indexers (AusSI)
http://www.aussi.org/
Classification Society of North America (CSNA)
http://www.pitt.edu/~csna/
Indexing and Abstracting Society of Canada / Societe Canadienne pour l'analyse de documents (IASC / SCAD)
http://www.indexingsociety.ca/
International Society for Knowledge Organization (ISKO)
http://is.gseis.ucla.edu/orgs/isko/
National Federation of Abstracting and Information Services (NFAIS)
http://www.nfais.org/
Society of Indexers
http://www.socind.demon.co.uk/
Society of Knowledge Base Publishers
http://www.montague.com/society.html
Software & Information Industry Association (SIIA)
http://www.siia.net/
Special Libraries Association (SLA)
http://www.sla.org/