The fundamental document of the Conference on Security and Co-operation in Europe, the Helsinki Final Act, was adopted by the original 35 participating States at the first CSCE Summit, which took place in Helsinki from 30 July-1 August 1975.
During the next 15 years, the multilateral process initiated in Helsinki was further developed at three follow-up meetings, known as Review Conferences.
The second CSCE Summit, held in Paris in November 1990, laid the foundations of the institutionalization process. Five subsequent Summits were held in Helsinki 1992, Budapest 1994, Lisbon 1996, Istanbul 1999 and Astana 2010. Each of these events produced declarations and documents that are important milestones in the history of the Organization.