Designed as a learning tool for those with limited background in quantum mechanics, this book provides comprehensive coverage of angular momentum in quantum mechanics and its applications to chemistry and physics. Based on class-tested material, this presentation offers clear explanations of theory while giving equal attention to solving real problems. Theoretical considerations are made concrete and accessible through extensive examples and applications at the end of each chapter. Problem sets, designed as both individual and group exercises, are treated as an integral part of the text in order to stimulate student interest and clarify the abstract principles discussed. Examples are drawn primarily from atomic and molecular phenomena, and include many intermediate steps (often left out of other texts) to ensure complete mastery of the material, and to lay the groundwork for understanding photon and particle collision phenomena, and more advanced studies. The new edition adds section and chapters on Runge-Lenz vector, Orientation and Alignment has been expanded into a chapter and includes angular momentum Interference effects in photodissociation) and reaction stereodynamics. A new chapter on vector-model wavefunction can be used to give quantitative and pictorial descriptions is also included.