Advocates of unions frequently argue that unionization results in benefits for libraries in general and for librarians. Previous data to support this position have been scattered, incomplete, and inconclusive. This study analyzes data on 1,904 academic libraries, 334 unionized, to explore whether there is a relationship between a librarian-union presence and several quantitative values: student-librarian ratios, percentage of institutional budget devoted to libraries, average spending on salaries per librarian, percentage of library budget devoted to librarians, percentage of library staff who are librarians, and percentage of library budget devoted to staff salaries. Across institution degree levels (associates, baccalaureate, masters, doctoral, and Association of Research Libraries members), results show that compared to librarians at either private or nonunionized public colleges and universities, librarians at unionized public institutions are somewhat better off. Librarians at public institutions are generally better paid but have worse working conditions--higher student-to-librarian ratios and fewer resources for collections. All institutions except associates-level institutions receive roughly the same percentage of institutional budgets.