This textbook is designed for undergraduate course in Compiler Construction for Computer Science and Engineering/Information Technology students. The book presents the concepts in a clear and concise manner and simple language. The book discusses design issues for phases of compiler in substantial depth. The stress is more on problem solving. The solution to substantial number of unsolved problems from other standard textbooks is given. The students preparing for GATE will also get benefit from this text, for them objective type questions are also given. The text can be used for laboratory in Compiler Construction Course, because how to use the tools Lex and Yacc is also discussed in enough detail.