This book is a comprehensive guide on neural stem cell behavior in health and disease. The book confers the altered behavior of endogenous neural stem cells in neurodegenerative disease conditions and the prospects of neural stem cell therapy for alleviating brain dysfunction in a variety of neurodegenerative disorders. Neural stem cell activity and neurogenesis in the adult brain is now confirmed in virtually all mammalian species including humans. Hence, a series of chapters in the first half of the book discusses the current knowledge on mechanisms of neural stem cell activity, the extent and functional significance of neurogenesis in the adult brain under normal, aged and disease environments, the susceptibility of neural stem cells and the plasticity of neurogenesis to alcohol, drugs of abuse and anesthetic agents, and advanced techniques that trigger neurogenesis in non-neurogenic regions. A second series of chapters in this book are focused on discussing the promise and efficacy of grafting of neural stem cells and/or other stem cells for treating neurological disorders such as Parkinson's disease, stroke, temporal lobe epilepsy, Alzheimer's disease and spinal cord injury. The final chapter confers on advances that are made in manufacturing a variety of neural cell types from human pluripotent stem cells that can be used as donor cells for cell transplantation.