Library co-operation has moved from an informal supporting role for individual library services to that of a major strategic instrument in the organization of available national resources to meet client needs. The pressure on financial resources, the development of technology, the growth in publishing output and the demand for access to it, have all contributed to the case for more effective forms of library co-operation, which can be seen at international, national, regional an local levels. These initiatives and links are also moving co-operation away from library-to-library relationships into a new area of co-operation with public, private and voluntary agencies. This book attempts to describe assess and evaluate co-operative schemes at all these levels, and looks to their continuation and development in the 1990s.