It has been demonstrated through previous demand analysis that the subject-oriented service system in university libraries are in higher demand than the function-oriented system. Despite of the increasing number of studies that prove cost-effectiveness and operational efficiency of the subject-oriented library service, there are virtually no university libraries in Korea that fully operate subject-oriented service. This study aims to propose a set of practical guidelines for university libraries to introduce subject-oriented service in the midst of many existing constraints, namely staff shortage. The study describes responsibilities of subject specialist librarians and analyzes best practices of subject-oriented service. Also it shows current standing of university libraries of difference size based on web site research of four-year university libraries.