The transition from print to e-resource collections has created unprecedented potential for libraries to collaborate in the collation and analysis of use data. This presentation will consider how libraries can harness this potential to better understand and enhance return-on-investment for their e-journal subscriptions. Specifically, it will discuss two projects within the University of North Carolina (UNC) system through which the system libraries shared use data to make cross-institutional analyses of expenditures, use, and cost-per-use (CPU). The first project, initiated by one of the presenters in the early 2011, centered on the analysis of e-resource CPU data shared among four UNC libraries. The second project was participated in by all UNC system libraries in May of 2012 and resulted from a mandate issued by the UNC General Administration to compare the expenditures for and use of the system libraries’ journal subscriptions. Throughout the discussion of these projects, the presentation will emphasize the opportunities and challenges of collaborative analysis of e-journal use data.