CiNii (Citation Information by National Institute of Informatics) is a bibliographic information system for scholarly journal articles, with which users can (1) search article citations originally from various databases, covering ca. 17,000 journal titles in 8 million articles; (2) view photographic image of the full-text articles for ca. 1500 journal titles in 2 million articles; (3) trace articles that were referred to in the article, and trace articles that cite the article, covering ca. 1200 titles in 0.8 million articles. As a periodical index to Japanese academic journal as well as an access to full text articles from some journals, CiNii, at present, is the only resource that provides full text access to Japanese journal articles.