Aðgerðarannsóknafélag Íslands: Icelandic Operations Research Society (ICORS).
AIRO: Italian Society of Operations Research, Optimization and Decision Science. Includes membership, meetings, and publications.
Australian Society for Operations Research (ASOR): Membership, meetings, resources.
Canadian Operational Research Society/Société Canadienne de Recherche Opérationnelle: Bulletin, meetings, careers, membership information and other resources. French and English site.
Dansk Selskab for Operationsanalyse: Danish OR society.
Gesellschaft für Operations Research e. V.: German OR society.
Hungarian Operations Research Society: Publications, meetings, jobs and other resources.
INFORMS: Institute for Operations Research and the Management Sciences. American OR society.
Netherlands Society for Statistics and Operational Research: VVS: Vereniging voor Statistiek en Operationele Research / Netherlands Society for Statistics and Operations Research.
Operational Research Society: United Kingdom OR society.
Operational Research Society of New Zealand: Membership, meetings, resources.
Operational Research Society of Singapore: Membership, meetings, jobs, resources.
ORBEL: Begian Operations Research Society - proposes an agenda of conferences as well as teaching information on O.R.
ORSSA: South African OR society.
ROADEF: French OR society.
S.E.I.O.: Spanish OR society.
Suomen Operaatiotutkimusseura ry: Finnish OR society.
The Operational Research Society - Study Groups & Regional Societies: Details of news, forthcoming presentations and study materials of regional branches of the society.