This book is a modern account of advanced classical electrodynamics, intended as a textbook for last year's undergraduate or postgraduates working for their PhD. The emphasis is on the fundamental properties of the EM field, such as symmetries. Both non-relativistic and fully covariant theory is covered, including a relativistic Lagrangian and Hamiltonian description of the interaction between charges and the field. The book has a comprehensive mathematical appendix covering both real and complex vector and tensor analysis.