E-book is the latest in information technologies that relate directly to books and reading. Although there are many kinds of e-books, such as downloadable e-books, dedicated e-book readers, Web-accessible e-books, Print-on-demand books, CD-ROM e-books, etc, and the e-book technology is still developing, the impact of e-book on publishing, libraries and readers are to be sure. No matter librarians like it or not, e-books are in existence in our society. Libraries need to keep an eye on the e-book evolution and to explore the most cost-effective and efficient ways to bring this new technology to their patrons.