从70年代后期以来,随着美国社会的信息化进程,美国图书馆界的外部信息环境发生了一系列的深刻变化。比如,信息中介业的快速发展、信息的商品化和市场化、信息的有偿服务、政府部门信息处理和运营的私有化等等。这些变化都给图书馆带来一些新的问题和挑战。如何理解和适应这些变化,美国的图书馆情报学界明显地形成了二种对立的理论思潮。一种认为,不论美国社会的 Since the late 1970s, with the process of informationization in American society, a series of profound changes have taken place in the external information environment of the American library community. For example, the rapid development of information intermediary, the commercialization and marketization of information, the paid information service, the privatization of government information processing and operation, and so on. All these changes have brought some new problems and challenges to the library. How to understand and adapt to these changes, the United States of the library and information science clearly formed two kinds of opposing theoretical trend of thought. One thinks, no matter American society