In this book, the authors discuss the stages, mechanisms and clinical outcomes of embryo development. Topics include chick embryogenesis as a unique platform to study the effects of environmental factors on embryo development; molecular and cellular aspects of blastocyst dormancy and reactivation for implantation; limb development and the emergence and function of the apical ectodermal ridge; and the use of time lapse photography in an in vitro fertilization program for better selection of embryo transfer.