Since the publication of the first edition of this book in 1989, the field of nonlinear fiber optics has virtually exploded. The third edition is intended to bring the book up-to-date so that it remains a unique source of comprehensive coverage on the subject of nonlinear fiber optics. An attempt was made to include recent research results on all topics relevant to the field of nonlinear fiber optics. Nonlinear Fiber Optics, Third Edition provides a comprehensive and up-to-date account of the nonlinear phenomena occurring inside optical fibers. It retains most of the material that appeared in the first edition, with the exception of Chapter 6, which is now devoted to the polarization effects relevant for light propagation in optical fibers. The contents include such important topics as self- and cross-phase modulation stimulated Raman and Brillouin scattering, four-wave mixing, modulation instability, and optical solutons. A proper understanding of these topics is essential for scientists and engineers interested in various aspects of lightwave technology. Such an ambitious objective increased the size of the book to the extent that it was necessary to create a separate but complementary book, Applications of Nonlinear Fiber Optics, which is devoted to applications in the domain of lightwave technology. This revised edition of Nonlinear Fiber Optics should serve well the need of the scientific community including graduate students in Optics, Physics, and Electrical Engineering, engineers in the optical communication industry, and scientists working in fiber optics and nonlinear optics.