This article investigated the lives and careers of three great librarians in India, USA, and Korea: S. R. Ranganathan, Melvil Dewey, and Bong-Suk Park, respectively. It also explored their influences and contributions. Their births and early years, and marriage; college years; commitment toward librarianship and careers; achievements in other areas; personalities; and commemorative activities, among others, were analyzed. Their contributions to librarianship and library community in the general theory of library science, professional education, classification and cataloging, library administration and management, and library associations and library movement were also investigated. Special focus was on Bong-Suk Park, with a special regard to his unrealized dream for the Korean library community as well as insufficient estimation related to him and his achievements.