自1950年起，相關概念在資訊檢索研究中一直扮演重要角色。資訊檢索系統的主要目的在提供讀者〝相關〞文獻。因此，本文回顧該主題中幾位重要學者理念及趨勢。內容包括相關概念的重要性、定義、五個派別（系統目的導向、讀者導向、多面性導向、認知導向、讀者 中心導向）與未來發展。

　　　　　The concept of relevance has played a major role in information retrieval（IR）research since the 1950s. The goal of an IR system is to provide users with access to〝relevant〞documents. Therefore this paper re-examines the viewpoints of majors writers in the field, then introduces a new approach. It includes definition、importance、five approaches（the system-oriented approaches、the user-oriented approaches、the multidimensional approaches、the cognitive approaches、the user-centric approaches）and the future development.