This volume is based on lectures and contributed papers presented at the Eleventh Course of the International School of Materials Science and Tech- nology that was held in Erice, Sicily, Italy at the Ettore Majorana Center for Scientific Culture during the period 6-17 July 1986. The subject of the course was "Electro-optic and Photorefractive Materials: Applications in Sig- nal Processing and Phase Conjugation" . The fields of electro-optics and photorefraction...