隨著網際網路的蓬勃發展，網路資源日益豐富。為了因應多語言主題檢索的挑戰及資源共享，數個歐洲國家遂發起合作計畫，企圖在不 同的控制詞彙中，利用對映或鏈結的策略來達到線上目錄多語言主題檢索的目的。這些合作計畫包括MACS及MSAC等，使用者依所選擇的言，能檢索到不同語言但同樣主題範圍的所有資料。本文試從文獻的研讀，擬探討多語言主題檢索之涵義，並藉由國外計畫MACS與MSAC之比較分析，研探國內圖書館線上目錄未來實現多語言主題檢索之可行性。

Since the Internet has become a new challenge of multilingualism and for resources sharing, several countries in Europe have created collaborative projects aiming to provide multilingual subject access to library catalogs. The projects will enable users to search simultaneously with a single query in the language of their choice for all relevant documents. This article describes the backgrounds of the projects such as MACS and MSAC, and explores a few suggestions for the future developments in multilingual subject access to our library catalogs.