In recent years, it has become clearly recognized that many behavioural disturb­ ances and psychiatric illnesses are intimately associated with alterations in neuroendocrine function. This volume is designed to provide a thorough, up-to­ date review of our current knowledge of the neuroendocrine correlates of altered behaviour in man and experimental animals. Particular emphasis has been focused on the mechanisms which may underlie the coupling of mental functions with endocrine changes and the possible common links in the central regulation of both endocrine and psychic activities. One of the main objectives of this book is to consider both the experimental and clinical approaches in studying the interrelationship between neuroendocrine regulation and altered behaviour, and to assess its importance in the pathogenesis, diagnosis and treatment of mental disorders. The book has been organized into four major sections which focus on: (i) the role of pituitary hormones in the regulation of CNS function; (ii) the relationship between brain endorphin systems, psychotropic drugs and neuroendocrine regulation; (iii) the importance of neuroendocrine regulation in the pathogenesis of mental disorders; and (iv) biological markers of altered mental function. Each chapter is organized for ease of comprehension as well as for rapid retrieval of progress and essential information concerning the neuroendocrine basis of altered behaviour and psychiatric illnesses. The contributing authors were selected because of their widely recognized expertise in the field.