The author is one of the prominent researchers in the field of data envelopment analysis (DEA), a powerful data analysis tool that can be used in performance evaluation and benchmarking. This book is based on the author's years of research and teaching experiences. It is difficult to evaluate an organization's performance when multiple performance metrics are present. The difficulties are further enhanced when the relationships among the performance metrics are complex and involve unknown trade-offs. This book introduces data envelopment analysis (DEA) as a multiple-measure performance evaluation and benchmarking tool. The focus of performance evaluation and benchmarking is shifted from characterizing performance in terms of single measures to evaluating performance from a multidimensional systems perspective. Conventional and new DEA approaches are presented and discussed using Excel.