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The Alliance's Strategic Concept,
Washington, 24 April 1999

 
 

The Purpose and Tasks of the Alliance

Deterrence and Defence: To deter and defend against any threat of aggression against any NATO member state as provided for in Articles 5 and 6 of the Washington Treaty. 

And in order to enhance the security and stability of the Euro-Atlantic area: 

Crisis Management: To stand ready, case-by-case and by consensus, in conformity with Article 7 of the Washington Treaty, to contribute to effective conflict prevention and to engage actively in crisis management, including crisis response operations. ()