Purchasing books on demand as a result of interlibrary loan requests has become a common occurrence at many libraries. There are various models for doing so, from involving collection developers and acquisitions staff to the ILL staff handling the entire process. The efficacy of such programs has been concluded from multiple published studies after a few years of running the service, but how does the use of the purchased books fair over a longer period? The results of an analysis of 15 years of POD ILL circulation data will be presented.