This work attempts to provide a comprehensive treatment of the topic of statistical inference under inequality constraints, in which much of the theory is based on the principles ofr maximum likelihood estimation and likelihood ratio tests. The book contains treatments of the topics of isotonic regression, tests of ordered hypotheses (including contrast tests and distribution free tests), inferences about multinomial parameters, duality, inferences for distributions subject to shape restrictions, conditional expectations given o-lattices and other subjects. Each chapter concudes with a section that discusses historical material and research which is related to the topics covered in the chapter but not discussed in detail in this book. An extensive reference section lists over 800 references on the topics included in the book and examples, figures, tables and discussion are provided to assist the reader.