For this volume the target audience is students who wish to learn about relativistic quantum field theory applied to particle physics, however, it is still very accessible and useful for students of condensed matter. This volume begins with the introduction of the path integral formalism for non-relativistic quantum mechanics and then, using this as a basis, extends the formalism to quantum fields with an infinite number of degrees of freedom. Dr. Strickland then discusses how to quantize gauge fields using the Fadeev-Popov method and fermionic fields using Grassman algebra. He then presents the path integral formulation of quantum chromodynamics and its renormalization. Finally, he discusses the role played by topological solutions in non-abelian gauge theories.