This work shows, discusses and shows the role and importance of the school library as the central place in school and as the informative, media and communications centre which, along the borrowing of books, gives the possibility to participate in numerous educational activities (projects, creative and pedagogic workshops, short educations, quizzes, literary meetings, competitions in knowledge and skills etc). This thesis describes school libraries in the past and characteristics of the modern school libraries. Further on, factors that influence the success of the library, material resources that need to be fulfilled to make a successful library, such as financial resources available to the library, space, equipment and fund are discussed. Further discussed are human resources crucial for the functionality of the library, such as the librarian and the other employees of the school and the principal. In this thesis, possible forms of cooperation between the librarian and the teachers, professional associates and the principal are suggested. The competencies of the successful school librarian (professional, personal and social) are given. The second part of the thesis describes the school library of the Czech elementary school Josip Ružička as an example of successful school library that implements numerous projects by which it is recognizable. Specifics of the library are further described, as well as the importance of cooperation between the librarian and other school employees. Also mentioned are the most important projects run by the school library.