Introduction to Quantum Field Theory
Shau-Jin Chang
World Scientific Pub Co Inc
This book is suitable for those meeting the subject for the first time- graduate students in theoretical physics take note.  Divided into two parts: Part 1 on General Field Theory and part 2 on Advanced Field theory, it treats both parts competently. Part 2 kicks off with a good discussion of Schwinger's Action Principle and includes a very good treatment of Path Integrals. Part 1 is mainly the usual canonical field theory, Feynman diagrams, QED, but also includes the application of the diagrammatic techniques to the many-body system.  This addition is nonconventional and is welcome.  However two cautionary remarks: Calculations are sparse and there are no problems at the ends of the chapters.  You need to rectify that by resorting to a text like the one by Peskin and Scheroder.  Secondly there are quite a number of typographical erros...not very serious and might hopefully be eliminated in future editions. I like this book!