In this book Peter Lee provides a complete description and survey of the field of semantics based compiler generation and presents a new method for expressing the formal semantics of programming languages that allows realistic compilers to be generated automatically. The method Lee describes has two main advantages over previous methods. First, it allows compilers to be generated automatically. The compilers are realistic in the sense that they compile programs as efficiently as hand crafted compilers do, and the object programs they produce run as efficiently as the object programs produced by hand crafted compilers. The second advantage is that it makes it easier to comprehend and write the semantics than other methods. The book demonstrates a working compiler generator called MESS which is used to generate a realistic compiler for a Pascal-like language. The generated compiler is then compared with several hand crafted compilers and shown to have at least comparable, and in some cases superior, performance. Peter Lee is Assistant Professor of Computer Science at Carnegie Mellon University. Realistic Compiler Generationis included in the series Foundations of Computing, edited by Michael Garey and Albert Meyer.