Book excerpt: This reference is completely revised and expanded to reflect the most critical studies, controversies, and technologies impacting the medical field, including probing research on lentivirus, gutless adenovirus, bacterial and baculovirus vectors, retargeted viral vectors, in vivo electroporation, in vitro and in vivo gene detection systems, and all inducible gene expression systems. Scrutinizing every tool, technology, and issue impacting the future of gene and cell research, it is specifically written and organized for laymen, scholars, and specialists from varying backgrounds and disciplines to understand the current status of gene and cell therapy and anticipate future developments in the field.