Stem cell transplantation and, in general, cellular therapies currently represent one of the highest frontiers in cancer as well as regenerative medicine. In the last decades, basic and clinical research on stem cells has dramatically increased, leading to effective, innovative treatments for a variety of patients. This book will aim to cover a wide range of themes linked to breakthroughs and innovations in cell-based therapeutics, with basic, pre-clinical, and clinical chapters written by well-known academics active in stem cell studies and research all around the world. It is intended to supplement and broaden the basic knowledge of hematopoietic stem cell transplantation and to include stem cell biology, immunogenetics, neuron replacement therapy, clinical issues, advanced HLA typing, alternative donor sources, and gene therapy that employs novel methods in this field. Tissue engineering, which uses revolutionary ways with stem cells, will also be investigated. The most recent advancements in cellular therapies, that currently flank stem cell applications, such as the Chimeric Antigens Receptor Cells-T (CAR-T) will be also discussed, representing one of the most intriguing therapeutic approaches in hemato-oncology.