Recent penetration of the Internet in every aspect of society is remarkable. Along with various types of access methods being developed, information contents and services provided through them have also become available in a broad variety. The mobile phone systems capable of accessing the Internet have become very popular in Japan in the past three years, and the services dedicated to mobile Internet access show a rapid increase. Now library services appear to be within the scope of the mobile Internet. This paper summarizes the development of the mobile Internet, the "i-mode," in Japan which has made it the number one country in the world in this area, and introduces the typical library applications involved. Statistics indicate the trend of usage for "i-mode OPACs" or mobile access services to library catalogs. The expectation for the future expansion of library applications in the area is considered to formulate a vision for the innovative library services of the new century. Illustrations of the menu and sample screens of Toyama University Library's I-Book Service are provided. The document "Mobile Access to Libraries: Librarians and Users Experience for 'i-mode' Applications in Libraries" (which includes 34 "thumbnail" pages of illustrations, charts, figures and tables) is provided at the end of the paper. Includes four tables and one figure. (Contains eight references.) (Author/AEF)