The study provides an analysis of U.S. academic library spending, staffing and utilization trends from data collected during the period between 1998 and 2008. Data used in this study are part of the NCES biennial survey of approximately 3,700 degree-granting postsecondary institutions. Confirming previous studies, there has been an order of magnitude change in the expenditure of e-books and e-serials; but, contrary to the view of being fiscally restrained, libraries have received investments and increases of approximately 12 percent above inflation over the period with significant increases in nearly every area of library operation. Library staffing is being diversified, while use of physical library assets are in decline for every metric in the study--gate count, reference service, general and reserve circulation. Academic libraries cannot be treated as a homogenous group of institutions, and the study analyzes shifts by type, size, and Carnegie class of institution, illustrating significant difference among these classes of academic libraries, particularly among large doctoral institutions and other academic libraries, with large public and doctoral private institutions driving growth, while small and medium-sized academic libraries have fallen behind in both collections and staff investments.