The Molecular Genetics of Vertebrate Development Unit (U 784), was created by INSERM in 2006, as a continuation of Unit 368, initially established in 1993, within the Department of Biology at the Ecole Normale Supérieure. From the beginning, this research unit has included two teams, respectively headed by Patrick Charnay and Frédéric Rosa, the research of which is centred on the molecular analysis of patterning and determination during early vertebrate development using complementary animal models such as chick, mice and zebrafish. The Department of Biology hosts approximately 300 people within one building. It is organised into 2 IFRs (Institut Fédératif de Recherche), including 6 research Units, either CNRS or INSERM, consisting of 20 different groups. Most of these groups are working in the related areas of Molecular Genetics, Developmental Biology and Neurobiology. The Department provides a number of central services and equipment including computing facilities and DNA analysis software, photographic and infographic services, electron and confocal microscopy, animal house and histology facilities, mouse gene knock-out service, RNA profiling service, etc... During the last few years, the two Unit teams have investigated the molecular and cellular mechanisms governing nervous system development, including the characterization of a population of stem cells (Charnay's group) and that related to the acquisition of specific fates and associated behaviour by embryonic cells, under the influence of extracellular signals (Rosa's group).