Studies of selected model organisms have led to a greatly improved understanding not only of the molecular events which take place during development under the control of specific sets of genes, but also of epigenetic and environmental influences on these processes. This book gives an overview of all three of these levels and their relative importance, and as such will give the reader a clear picture of one of the most exciting areas of current biological research. TOC:Section 1: Microbial Systems, Both Prokaryote and Eukaryote Virus Assembly and Morphogenesis; Spatial and Temporal Control of Gene Expression in Procaryotes; Multicellular Development in the Myxobacteria Myxococcus xanthus and Stigmatella aurantiaca