The Treaty on Open Skies, which set out the framework for a regime of unarmed observation flights over the territory of participating States, was signed in Helsinki on 24 March 1992.
Although the Treaty was not negotiated within the CSCE/OSCE framework in its formal sense, it is nevertheless closely associated with the Organization due to its basic philosophy of openness.
In the text of the Treaty, the States Parties recalled their CSCE commitments "to promoting greater openness and transparency in their military activities and to enhancing security by means of confidence- and security-building measures."
They further noted that the creation of the Open Skies regime for aerial observation was motivated by the wish "to contribute to the further development and strengthening of peace, stability and co-operative security."
It would also facilitate the monitoring of compliance with existing or future arms control agreements and strengthen the capacity for conflict prevention and crisis management within the framework of the CSCE.
In a Declaration issued at the same time in Helsinki, the CSCE Ministers of Foreign Affairs welcomed the signing of the Treaty and recognized "the importance of the Open Skies régime for the security of States participating in the CSCE process."
They also assessed the Treaty as "an important element in the process of enhancing security and confidence between members of the international community," and reiterated the importance of the principle of equal security for all countries.
The Treaty on Open Skies entered into force on 1 January 2002, 60 days after the necessary number of ratification documents was received. Thirty-four countries are currently States Parties to the Treaty.
There is also an Open Skies Consultative Commission, the central focus of which is to discuss questions relating to compliance with the Treaty's provisions.