at the University of Pittsburgh, which also supported the symposium. The present volume was developed from papers originally presented there. My strategy in editing this book has been to focus upon the vestibular end organ and its direct connections. both peripheral and central, in order to as­ sure a coherent discussion of the basics of vestibular function, structure, and ultrastructure. Fortunately, it was possible to secure the contributions of a number of outstanding investigators from both the United States and abroad, including functionally oriented morphologists. ultrastructuralists, biophysicists, and vestibular physiologists. The result is a comprehensive discussion of the main mechanisms of the labyrinth: the transduction pro­ cess at the receptor level, in the semicircular canals, and in the utricular and saccular maculae; the information transfer through neuronal pathways to the nuclei and the cerebellum; and the general organization of the system.