This book introduces the reader to the main quantitative concepts, methods, and computational techniques needed for the development, evaluation, and application of tests in the behavioral/social sciences, including educational tests. Two empirical examples are carried throughout to illustrate alternative methods. Other data sets are used for special illustrations. Self-contained programs for confirmatory and exploratory factor analysis are available on the Web. Intended for students of psychology, particularly educational psychology, as well as social science students interested in how tests are constructed and used, prerequisites include a course on statistics. The programs and data files for this book can be downloaded from www.psypress.com/test-theory/