AbstractBell Telephone Laboratories has established an on-line circulation system linking two terminals in each of its three largest libraries to a central computer. Objectives include imporved service through computer pooling of collections, immediate reporting on publication availability or a borrower's record, automatice reserve follow-up; reduced labor; and increased management information. loans, returns, reserves and many queries are handled in real time. Input may be keyboard only or combined with card reading, to handle all publications with borrower present or absent. BELLREL is now being used for some 1500 transactions per day.