Lecture, four hours. Requisite: course 230A. Perturbative methods for quantization of interacting quantum field theories. Topics include functional methods in scalar field theory, perturbation theory for scalar field theory, Feynman rules, UV regularization and renormalization, perturbation theory for quantum electro-dynamics (QED), Ward identities, renormalization of QED, and anomalies in QED. S/U or letter grading.