Light-matter interaction is pervasive throughout the disciplines of optical and atomic physics, condensed matter physics, electrical engineering, and now increasingly in biology and medicine with frequency and length scales extending over many orders of magnitude. Deep earth and sea communications use frequencies of a few tens of Hz, and X-ray imaging requires sources oscillating at hundreds of petaHz. This book provides advanced undergraduates, graduate students and researchers from diverse disciplines with the principal tools required to understand and contribute to rapidly advancing developments in light-matter interaction, centred at optical frequencies and length scales from a few hundred nanometres to a few hundredths of a nanometre. This book deploys an arsenal of powerful analytic tools to render this multidisciplinary subject in unique form, not encountered in standard Physics or Electrical Engineering text books. This new edition has been substantially expanded with almost 200 pages of new material. Several new and extended chapters treat momentum flow between fields and matter, metamaterials, and atom-optical forces applied to atomic and molecular cooling and trapping.