This volume covers new aspects and future directions in molecular neuroendocrinology, an important and rapidly growing area in neuroendocrinology. Among the various neurotransmitters or neuromodulators that play an important role in the control of endocrine functions, neuropeptides and related proteins have drawn special attention because of their diversity and complexity in action. More recently, molecular biology has become an essential tool of research in this area. Various genes encoding neuropeptides and other related pro- teins have been cloned, and the regulation of expression of these genes has been studied extensively. Transgenic animals have been used in studying the function of the gene in que- stion. In-situ hybridization is being applied to localize the site of production and analyze the regulation of pro- duction of peptides or proteins.