Data of all relevant aspects of neuronal cell growth and differentiation are presented in this volume. Regulation of expression, storage and release of nerve growth factors, receptor control and the cellular responses to growth factors are comprehensively discussed. Treated are also influences of various neurotransmitters on neuronal morphogenesis and new results of interactions of cells and mediators of the immune, endocrine and nervous system. Special emphasis is given to those factors regulating regeneration and nerve spreading after injuries of the nerve tissue.