| 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. |
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