Beyond collecting traditional circulation statistics, tracking in-house use of library materials is a significant measure of how patrons use our resources. In our pilot project, Lending Services staff members conducted nightly pick-ups of library materials left on tables, in carrels, in study rooms, as well as books cast aside in the stacks areas as patrons browsed the book stacks. We obtained a two week sample of these "abandoned" materials, quantifying the in-house use by our patrons while also counting the routine work of our Lending Services department. (Contains 5 figures.)