Since the end of the war, librariarship in Japan have tended to put more emphasis on services rather than library materials. But no library service can be rendered without a good collection. To build a good collection, a well organized acquisition policy is indispensable.Any acquisition policy statement should make clear at least the following five factors: 1. objectives of the university; 2. objectives of the library; 3. the location of responsibility for selection; 4. the location of responsibility for the book funds; 5. those who participate in selection.The university library collection can be considered from the standpoint of the types of material in it; reference books, periodicals, books which reveal history and contemporary thought in all the subject fields that are studied in the curriculum, government documents, and recreational books. From the standpoint of the quality of the material, the library collection consists of classics, standard works, and special material for highly specialized research. From still other point of view, university library material can be divided into two great groups; those which extend the frontiers of knowledge and secondary or teaching materials such as texts, syntheses, introductory works, etc. More difficulties exist in selection of the first group of material.In the process of building a library collection, planning, putting the plan into practice, examination and evaluation of the results are a series of essential activities. Evaluation is a final stage and at the same a starting point. There is no single standard measuring device for evaluation, and several procedures should be used to obtain a more or less accurate picture of the status of the collection. The chief methods commonly used are: 1. a subjective or impressionistic method, asking opinions of persons who undertake evaluation, 2. check list method, i.e. check of holdings against standard lists and bibliogarphies, 3. identification of levels of collections, 4. check of current circulation records, 5. check of the records of materials requested and not in the holdings, and 6. check of the expenditures for libray materials.Nowadays many universities, especially private ones, are in extreme financial difficulty, and, since the library is expensive, it is often regarded as a burden to the university. But the same university thinks little of paying much money for the rental fee of a large computer or buying expensive laboratory equipment which will become obsolete very soon. The research library never becomes obsolete and is a permanent investment of the university. Bearing this in mind, the librarians should take courage in building a good library collection for both present and future needs.