This book presents an advanced treatment of classical electromagnetism that expands on the central content and methods of the theory. It emphasizes the core ideas of electromagnetism in a way that provides new insights into physics and the applied mathematics in which it is expressed. The book presents the theory in a form that relates electromagnetic fields to their charge and current density sources as directly as possible based on Green's functions and relatively easily interpreted integral equations, Jefimenko's equations. Electromagnetism is more than Maxwell's equations or the integral equations for the electromagnetic fields: the charge and current density sources are governed by their own equations of motion which are compatible with Newton's laws of motion including electromagnetic forces. These forces depend in turn on electromagnetic fields. This mutual and self-consistent interplay between the motion of the sources and the electromagnetic fields is a theme of this book.