Ventral and Dorsal Contributions to Hematopoiesis in Xenopus -- Genetic Dissection of Hematopoiesis Using the Zebrafish -- Extra- and Intraembryonic HSC Commitment in the Avian Model -- Avian Lymphopoiesis and Transcriptional Control of Hematopoietic Stem Cell Differentiation -- Yolk Sac Development in Mice -- Long-Term Reconstituting Hematopoietic Stem Cell Capacity in the Embryo -- The Endothelium: The Cradle of Definitive Hematopoiesis? -- Endothelial and Hematopoietic Cells in the Intraembryonic Compartment -- Origin and Fate of Hematopoietic Precursors in the Early Mouse Embryo -- Hematopoietic Development in Drosophila: A Parallel with Vertebrates -- Intraembryonic Development of Hematopoietic Stem Cells during Human Ontogeny: Expression Analysis -- Gene and Cell Therapy Involving Hematopoietic Stem Cell. Hematopoietic Stem Cells brings together articles covering the biology of hematopoietic stem cells during embryonic development, reporting particular aspects of fly, fish, avian and mammalian models. Thus, this book allows a comparative overview of hematopoietic stem cell generation in the different classes, emphasizing the conserved trends in development. This book culminates with state-of -the art knowledge on hematopoietic development in human species and discussions of the most recent breakthroughs with relevance to both researchers and clinicians.