The field of the neurosciences is one of the most rapidly growing in present biological research. Its molecular aspects are dealt with by the discipline of neurobiochemistry. As the theme of the Mosbacher Colloquium, we chose this term rather than the term "neurochemistry", in order to stress the dynamic biochemical aspects of present molecu lar neurobiology and to avoid the flavor of being purely descriptive and "static", which is frequently associated with the term neurochem istry. This appears the more warranted, since the natural products and analytical chemistry phase of discovering the basic chemical com ponents of the nervous system has passed its culmination. The period of assessment has laid the foundation for studying the dynamic inter play of the various chemical components in the actual biological opera tion of nervous tissue. Thus, neurobiochemis~ry is that part of the neurosciences which is dominated by the ways of thinking and the metho dology of biochemistry. For this Colloquium only topics were selected that deal with the biochemistry of neurons. Thus, we excluded from the agenda other neu ral cells such as glial cells (astrocytes, ependymal cells, oligoden drocytes), meningeal cells, and capillary endothelial cells. This restriction was applied for two reasons: (1) The time available for the meeting did not allow an extensive display of the whole spectrum of neurobiochemical research. (2) The biochemistry of neurons is far more advanced than that of any other cell type of the nervous system •.