During the decade since the publication of McLaren's Mammalian Chimaeras (Cambridge University Press, 1976), the field of mammalian embryology has undergone tremendous expansion and diversification. There is now a substantial body of information available on cellular, biochemical, and molecular aspects of the early embryo, and exciting new approaches to the genetics of development are now possible through recombinant DNA techniques. Yet during this period of rapid growth there has been no single volume summarizing these advances. This book is our attempt to remedy this deficiency.

The book is intended for any serious student of the mammalian embryo and should be useful at many levels. Advanced undergraduates and graduate students can learn from the authors' emphasis on general principles; established investigators of mammalian development will benefit from the attention to detail. Developmental biologists working in other systems will enjoy the opportunity for cross-species comparisons. For the many molecular biologists who have discovered the mouse embryo in their quest for transgenic mice it will provide an introduction to the wider issues of mammalian embryogenesis. Scientists working in the more applied areas of embryology, such as human in vitro fertilization and livestock embryo manipulation, can contemplate applications of new experimental techniques to their systems.

The goal of a readable, affordable book has required some compromises. We have omitted the topics of fertilization and embryo transfer because these have been covered recently in other reviews. We have also omitted discussion of aspects of later embryonic development, such as lineage analysis of the nervous system and sex differentiation, so that we could concentrate on events in the early stages of development before and just after implantation.