The Organization for Security and Co-operation in Europe (OSCE) is the largest regional security organization in the world with 55 participating States from Europe, Central Asia and North America. It is active in early warning, conflict prevention, crisis management and post-conflict rehabilitation. The OSCE has a comprehensive approach in dealing with range of security-related issues including arms control, preventive diplomacy, confidence- and security-building measures, human rights, democratization, election monitoring and economic and environmental security.

Irish Aid has supported the OSCE in Bosnia-Herzegovina through funding for OSCE Political Resource Centres in Banja Luka and Bihac in 2002. Assistance is also provided to the OSCE office in Macedonia. The Office for Democratic Institutions and Human rights (ODIHR) is the principal institution of the OSCE responsible for the human rights dimension (based in Warsaw, Poland). ODIHR is active throughout the whole OSCE area. Irish Aid provides ongoing support for the ODIHR officer responsible for promoting freedom of religion and tolerance.