The DIJ library is a reference library with open-access shelving. Since reference books are arranged according to Nippon Decimal Classification (NDC) and the central holdings are shelved by order of accession, the best access method is to search the online public access catalog (OPAC) on the Web. Open-stack shelving allows the user direct and fast access to books, periodicals and reference works. Although the DIJ library has the status of a reference library, it is also a regular member of the Japan Special Libraries Association (Senmon Toshokan Kyôgikai) and participates in the interlibrary loan service within Japan as well as internationally.