由各會員國國家元首或政府首長組成的歐洲聯盟高峰會是歐盟最高的決策機構。但這一個「提供歐盟發展必要的動力」和「界定一般的政策指導與優先性」的機構，卻不是歐盟的初創機構之一。相反的，它正式出現於共同體成立二十年後，成為體制內的機構是再一個二十年後的事。類似於高峰會的發展，共同安全暨防衛政策也是歐盟發展史上晚近的政策一，正式納為歐盟的政策時，該政策已在歐盟體制外存在將近四十年的時間。共同體成立四十年後，高峰會和共同安全暨防衛政策相繼成為歐盟體制內的機構與政策，兩者的納入既是統合論的發展必然，也標誌著歐洲統合的一大里程碑。本文首先以歷史分析的角度，分別檢視高峰會和共同安全暨防衛政策的發展軌跡；其次分析高峰會在該政策內的角色與功能；第三探討輪值主席與常設主席對該政策的影響，最後是本文的結語。

Be composed of the Heads of State or Government, the European Council is the highest decision-making institution of the European Union (EU). Although it provides the EU with the necessary impetus for its development and defines the general political directions and priorities, it is not the original institutions, which the Community has established from the beginning. As a unoffical institution, the European Council emerged twenty years after the birth of the Community, it takes another twenty years until it become the formal institution. Like the European Council, the Common Security and Defence Policy (CSDP) is a policy which the EU recently develops. Since the Treaty of Brussels from1948, the security and defence policy has existed parallel to the Community more than forty years. 1992, the European Council and the CSDP become the formal institution and the official policy of the EU. The inclusion into the EU is not only the logical consequence from the views of the integration theory, but also sets up a milestone in the development of the European integration. This article firstly deals with the developments of the European Council and the ESDP from their beginning respectively. Second, it analyzes the role and functions of the European Council in the ESDP according to the European Treaty. Third, the role of the chairman-in-office and the permanent president of the European Council will be discussed. Finally, a conclusion will be made.