A convention signed in 1902 by the Mayor of Clermont-Ferrand, the Chancellor of the University and the Minister of Public instruction, made it possible to stock the books of the public and university libraries in the same building, under the University librarian's authority. The structure, very frequent in Germany, was the only one of this kind in France. The cooperation between public and university libraries, so judicious in an averagesized town, is here completely successful. Since then, the library has kept on growing in the same way by creating two research centres. Their collections, belonging to the town, are placed under the control of the University : the Henri Pourrat centre and the Blaise Pascal international centre. It has also been at the origin of the cooperation between the University library and the libraries of the Faculty of arts, thanks to its service of departrnent libraries set up in 1966, the creation of a rationalizing unit in 1976 and all sorts of activities whose task is to create union catalogues and other collective works.