``Field Theory in Particle Physics'' is an introduction to the use of relativistic field theory in particle physics. The authors explain the principal concepts of perturbative field theory and demonstrate their application in practical situations. The material presented in this book has been tested extensively in courses and the book is written in a lucid and engaging style. Many interesting problems are included at the end of each chapter, both to test the understanding of the subject matter and to further amplify the ideas in the text. The authors have taken great care to make their presentation as self-contained as possible by adding several appendices.