A recent rapid expansion in our knowledge of embryonic development in birds and reptiles has created a need for a book that comprehensively reviews and synthesizes data relating to incubation effects on the embryonic development of these two vertebrate classes. The contributors to this book aptly deal with these issues in logical parts. The first deals with the structure, shape, and function of eggs. The second examines the effects of the four main parameters, e.g. temperature, water relations, respiratory gas exchange, and turning, on the process of incubation. The third section deals with early embryonic development and the methods used to investigate and manipulate the embryo. Further chapters deal with estivation, megapodes, and oviparity.