Data Envelopment Analysis (DEA) has grown into a powerful, quantitative analytical tool for measuring and evaluating performance. This volume offers a systematic introduction to DEA and its uses as a multifaceted tool for evaluating problems in a variety of contexts. Each chapter illustrates its concepts with simple numerical examples and discussions of actual applications. The first nine chapters cover the basic principles of DEA, while the final seven chapters provide a more advanced treatment. For this new second edition, the final seven chapters have been completely revised, reflecting recent developments that have greatly extended the power and scope of DEA and have lead to new directions for research and DEA uses. This new edition systematically details both basic principles and new developments in DEA, offering a solid understanding of the methodology, its uses, and its potential.