Chapter 1: Introduction.- Chapter 2: Conceptual background: firms’ objectives, decision variables and economic efficiency.- Part I.- Chapter 3: Shephard’s input and output distance functions: cost and revenue efficiency decompositions.- Chapter 4: The generalized distance function (GDF): Profitability efficiency decomposition.- Part II.- Chapter 5: The Russell Measures: Economic Inefficiency Decompositions.- Chapter 6: The Weighted Additive Distance Function (WADF): Economic inefficiency decompositions.- Chapter 7: The enhanced Russell graph measure (ERG=SBM): economic inefficiency decompositions.- Chapter 8: The directional distance function (DDF): economic inefficiency decompositions.- Chapter 9: The Hölder distance functions: economic inefficiency decompositions.- Chapter 10: The loss distance function: economic inefficiency decompositions.- Chapter 11: The modified directional distance function (MDDF): economic inefficiency decompositions.- Chapter 12: The reverse directional distance function (RDDF): economic inefficiency decompositions.- Chapter 13: A unifying framework for decomposing economic inefficiency: The general direct approach and the standard and flexible reverse approaches.- Chapter 14: A final overview: economic efficency models and properties.- Bibliography.- Subject Index.- Author Index.