Art libraries are different from other libraries; they require of art librarians a broad knowledge of art, with a more detailed knowledge of any aspects of the subject in which the particular library has a special interest. This kind of knowledge cannot be acquired entirely from books, but must also be gained from direct encounters with works of art, and by immersing oneself in different places and cultures. Art librarians must also be prepared to learn about art librarianship from colleagues at home and abroad, and about the needs of library users from the users themselves. Yet on occasion the demands of users, as well as the meddling of administrators, must be resisted. Art librarians must apply their knowledge not only to the selection of books, but also to the provision and organisation of visual resources, and to assessing both the value and the limitations of databases. [An English version of this paper appeared in ARLIS NORDEN INFO 1992 no. 2/3; the French text is published here for the first time, and is followed by a new English translation].