| Abbreviation | Definition |
|---|---|
| CLEG | Central London Europe Group |
| CLOE | Clusters Linked Over Europe |
| CMEC | Cambridge Model European Council |
| CMIE | Centre Médical Interentreprises Europe |
| CMPD | Crisis Management and Planning Directorate |
| CNETU | Congress of Non European Trade Unions |
| CNETU | Council of Non European trade unions |
| COD | Cliffs Of Dover |
| COE | Council of Europe's |
| COGECA | COmité GEnéral de la Coopération Agricole (in French) General Committee for Agricultural Cooperation |
| COPA | Comité des Organisations Professionnelles Agricoles (in French) Committee of Agricultural Organizations |
| COPA | Comité des Organisations Professionnelles Agricoles (in French) Committee of Agricultural Organizationsn |
| COPE | Children Of Prisoners Europe |
| CoSIE | Co-creation of Service Innovations in Europe |
| COSINE | Cooperation for Open Systems Interconnection Networking in Europe |
| CPFE | Christian Political Foundation for Europe |
| CPGE | Conference of Prosecutors General of Europe |
| CPRE | Campaign to Protect Rural England |
| CPSU | Communist Party of the Soviet Union |
| CREAS | Center for Russia Europe Asia Studies |