Book excerpt: The field of stem cell biology is expanding with a continued surge of new information related to its applications. Over past few years, stem cells have been extensively used in cell therapy, tissue engineering, in vitro drug testing among others. At the moment there is no single book available which comprehensively describes the significance of various application of stem cells derived from embryonic and adult sources from lab to clinics. In this edited volume, we discuss basics and advanced topics of stem cells to help researchers, students and professional find the most important information in a single source of updated information about stem cells and relevant applications. This book is divided in 12 chapters and covers topics such as in vitro cell culture, 3D cell culture, cell therapy, tissue engineering, cell factory, cell functionality, in vitro drug testing, organ development, autologous transplantation, allogeneic transplantation, adult stem cells, multipotent stem cells, induced pluripotent stem cells, a pluripotent and embryonic stem cells.