自前蘇聯瓦解、前東歐共黨地區紛紛實施政治民主化、經濟自由化的改革以來，俄國及中歐、東歐國家的政治經濟改革及其發展局勢，近期逐漸成為歐洲研究焦點，波蘭、捷克、匈牙利三國已於一九九九年三月成為北約組織的會員國，其他前東歐共黨國家目前多數也在申請加入的名單之列。對中、東歐國家而言，國家安全至上是這些國家從歷史學習到的重要經驗，如何保障國家獨立自主成為此等國家上下一致的主要目標。從權力結構的角度出發，本文試圖探討中、東歐地區的權力真空狀態如何受到歐洲權力結構的影響，並進一步探討歐洲安全體系的建立，以及權力運作的若干可能結果。

　　　　　The historical record does not offer much comfort to Central and Eastern Europe when they consider how best to guarantee the security of their peoples. During the cold war period, Poland, Czech, and Hungry belonged to the Soviet bloc; nevertheless, with the collapse of Soviet Union, these countries soon shifted to the western bloc. The remaining countries still face power vacuums. According to the theory of realism, power vacuums will give rise to power competition; that is to say, the process the transformation of pre-communist bloc is confronting another round of power struggling. This research focuses on the transformation of this region. First, the paper will review the theory of realism and clarify some related concepts. Then it will extend the discussion to the three layers of analysis: hegemony, second- tier, and general system actors. At the same time the paper points out potential influential variables. The paper ends by drawing several conclusions.