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Open Skies Treaty

Fact Sheet on the Open Skies Treaty, U.S. State Department, May 18, 2009


The Treaty on Open Skies entered into force on January 1, 2002, and currently has 34 States Parties. The Treaty establishes a regime of unarmed aerial observation flights over the entire territory of its participants. The Treaty is designed to enhance mutual understanding and confidence by giving all participants, regardless of size, a direct role in gathering information about military forces and activities of concern to them. Open Skies is one of the most wide-ranging international efforts to date to promote openness and transparency of military forces and activities.

The Treaty is a complex instrument which establishes a regime for the conduct of observation flights over the territories of States-Parties to the Treaty, and regulates the technicalities, including, inter alia, the quotas for observation flights, based upon reciprocity between the States-Parties or groups of States-Parties; the notification of points of entry for observation flights for each State; the technical details for sensors (photo and video cameras, infra-red line scanning devices, and radar equipment) used for the purposes of conducting observation flights as well as their inspection by the State concerned; the designation and use of personnel and aircraft for observation flight, and the conduct during observation, including provisions to prohibit flights, or to change mission plans, or for emergency situations.

The Treaty further established the Open Skies Consultative Commission (OSCC) in Vienna as a body representing all States Parties to the Treaty, for further consultations, clarification of issues, and the proposal of amendments to the Treaty.

Primary documents, including treaty text and associated memoranda, statements and other related material.

Open Skies Glossary

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