This study, supported by Library Service and Construction Act Title III funds, was intended to investigate (1) the volume of library traffic between and among all Ohio campuses; (2) the kinds of libraries patronized by Ohio academic personnel; (3) the characteristics of those non-academic libraries which were patronized (or at least of those parts of their collections which were used); (4) the variations in extra-institutional (off-campus) use according to the characteristics of each "home" institution; (5) other patterns of use; and (6) a methodology which could be utilized in this study and tested for other uses. Basic to the investigation were the plans of the Ohio College Library Center. Both formal (ILL) and informal (personal) use of academic and other libraries were investigated. Study findings include: (1) a need for changes in interlibrary loan forms; (2) the sovereignty of Case Western Reserve University, The Ohio State University, Oberlin College and the University of Cincinnati as sources of library materials; (3) library activity outside of Ohio concentrated in the northeastern part of the U.S.; (4) Ohio academic personnel using libraries in Ohio more than those out of state; and (5) the need for further use studies and a review of the experience of academic libraries using teletype. An annotated bibliography of 178 items is appended. (Author/JB)