"The aim of this book is to cover the scope of Nanophotonics, a discipline that has emerged around the turn of the millennium. It results from the merge of different communities working in different aspects of light-matter interaction at the nanoscale. These include near-field optics and super-resolution microscopy, photonic crystals, diffractive optics, plasmonics, optoelectronics, synthesis of metallic and semiconductor nanoparticles, two-dimensional materials and metamaterials. Our feeling when we started the project was that a book covering most of these aspects altogether was lacking. The field is so rapidly evolving that it is impossible to summarize all the recent breakthroughs. The goal of this book is to provide a self-contained discussion of the fundamentals of the different subfields involved in nanophotonics. The current project is a collaborative project between three researchers that have been actively involved in the field from different communities. Henri Benisty has a background in semiconductor physics and optoelectronics, Jean-Jacques Greffet has a background in near-field optics and light scattering, Philippe Lalanne has a background in diffractive optics and photonic crystals. All of them made significant contributions to the advancement of the field. The book material is based on lectures that have been given by them at the Institut d'Optique Graduate School (Palaiseau, Bordeaux and Saint-Etienne)"--