This document discusses various issues relating to textbook usage and access in university courses. It poses questions about the maximum number of students one copy of a 7-day loan textbook could serve in a semester, as well as how many students a single copy is likely to actually reach. It also considers best and worst case scenarios for loan periods and returns. The document explores topics like collection development strategies, print versus electronic format costs and usage, and implications of relying primarily on e-resources for courses.