Filling the need for a textbook-level treatment of atomic physics, this volume presents in a coherent and comprehensive way the conceptual basis for the quantum theory, while at the same time providing an elementary introduction to the mathematical methods needed to relate the formalism of the theory to measurements in the laboratory. The author is a well-established and highly regarded theorist in atomic physics and assumes little previous knowledge in quantum mechanics and related topics on the part of the student. As well as covering the traditional areas of structure and spectra, he presents an overview of such topics as coincident studies of atomic collisions, atoms in intense laser fields, quantum information theory, and atom trapping, while also including a discussion of recent advances in atomic collision theory. A number of detailed case studies guide readers to the research literature, and an extensive set of problems and exercises aid teaching as well as self-study for upper undergraduate or graduate level students of physics.