This book is based on the NATO Advanced Research Workshop on "Mesenchymal-Epithelial Interactions in Neural Development" which was held in Berlin during March 1986. The idea that it may be the time for this workshop arose from a discussion among the organizers who met at a conference in Innsbruck. During the twenties, Spemann demonstrated that, in vertebrates, the formation of neuroepithelium depends on the induction by specific mesodermal derivatives. This was about the first time that mesenchymal-epithelial interactions had been recognized as an important mechanism in the development of an...