“江苏省工程技术文献信息中心”联盟是国内跨系统区域图书馆联盟建设比较成功的案例之一。文章分析了联盟取得成功的重要因素——资源、平台、人员、用户,这4个因素成为联盟成功的法宝。研究发现现有联盟在运行过程中仍然存在一些问题,并提出解决这些问题的相关对策,为国内同类联盟的建设发展提供参考。 “Jiangsu Provincial Engineering and Technical Documentation Information Center ” Union is one of the more successful cases of the construction of cross-system regional library alliance. The article analyzes the important factors of successful union - resources, platforms, personnel, users, these four factors have become a magic weapon for the success of the alliance. The research finds that there still exist some problems in the operation process of the existing alliance, and put forward some countermeasures to solve these problems, which can provide references for the construction and development of similar alliances in China.