Quantum Chromodynamics is a thorough introduction for students in theoretical physics and scientists needing a reference and exercise book in this field. The book presents the necessary mathematical tools together with many examples and worked problems. In introductory chapters the reader becomes familiar with the hadron spectrum, while the SU(N) symmetry groups and the relativistic field theory are briefly recapitulated; then a discussion of scalar quantum electrodynamics and scattering reactions follow before gauge quark-quark interactions, perturbational QCD, renormalization groups, and tests of pertubational QCD are all treated in detail. Chapters on non-perturbational QCD and quasi-phenomenological applications conclude the text.