The objective of this volume is to provide recent information on neural regulation in the endocrine system in vertebrates. Classical studies have revealed that certain neurons synthesize and release chemical messengers into the blood vascular system. These neurons are endocrine devices that link the brain with the endocrine glands and other target organs. In vertebrates the hypothalamus is the seat of chemical coordination and integration of environmental and hormonal cues to modulate function of the pituitary, and, consequently, the functions of other endocrine glands. Information generated during the past few decades has resulted in profound alterations in the conceptual fabric of endocrinology. From the wealth of information that emerged on neuropeptides of the central nervous system, and connectivities of various brain centers, it has become clear that several extra-hypothalamic sites are also involved in regulation of hypophysial hormones. This volume is divided into five sections: brain regulation of pituitary, brain GnRH and regulation of pituitary in fish, brain control of growth hormone in fish and birds, brain regulation in mammalian luteinizing hormone, and neural control of other endocrines and the immune system. It is hoped that this volume will prove useful to researchers, teachers, and students involved in research and teaching in neuroendocrinology and comparative endocrinology.