Recent developments in stem cell biology have opened new directions in cell therapy. This book provides the state-of-the-art developments in using biomaterials as artificial niches for engineering stem cells, both for the purpose of better understanding their biology under 3D biomimetic conditions as well as for developing new strategies for efficient long term maintenance and directed differentiation of stem cells into various therapeutic lineages. Animal and human stem cells of both embryonic and adult origin are discussed with applications ranging from nerve regeneration, orthopedics, cardiovascular therapy, blood cell generation and cancer therapy. Both synthetic and natural biomaterials are reviewed with emphasis on how material-stem cell interactions direct specific signaling pathways and ultimately modulate the cell fate. This book is valuable for biomaterial scientists, tissue engineers, clinicians as well as stem cell biologists involved in basic research and applications of adult and embryonic stem cells.