This book is 27th Volume of Comprehensive World History Series book project by the World History Institute of CASS, which was started in 2000s, which comprises 39 volumes altogether. The book is co-written by renowned scholars Zhou Rongyao, Jiang Nan, Jin Hai, who are researchers of Institute of World History attached to Chinese Academy of Social Sciences. Comprehensive World History Series is a pioneering project, which demonstrates the theoretical achievements of China's world history studies, and will certainly contribute to the international history academy. The book series is published by Jiangxi Publishing House, in Nanchang. We have started our publishing plan with the volume "The History of Western Alliance After the World War II-1945-2005" and the "International Relations Volumes" include 8 books. The reason to begin the International Relations Volumes with the "Western alliance" is because the author suggests that the world, its order and structure in the Post-War period (WW II) were maintained by various alliance systems. And during this era, the post-War Western alliance has been the most central and complete reflection of the relations between Western countries. All the aspects of international relationships are included in the book. The content of the book mainly concentrates on the issues of strategy, security, politics and economy which affect the overall relationship status among the Western powers. Based on a thorough analysis and research on the Western alliance, the book attempts to reveal the basic factors influencing the relationship between major developed countries and points out to those "lasting characteristics" "variations" "similarities" and "particularities" with special attention given to those factors more directly related with the overall situation.