Research in optical information technology in Europe hasbeen very active inrecent years. This volume recordsstate-of-the-art research conducted in some 22 laboratorieswho have worked together within EC ESPRIT Basic ResearchAction 3199 up to 1992. The topics cover:(1) Active optical logic and switching devices - embracingnew materials, nonlinear and electrooptic mechanisms as wellas advanced device fabrication. These devices cover therange from all-optical nonlinear interferometer structuresthrough hybrid optical-electronic modulators to integratedemitter-receiver structures.(2) The latest state of optical interconnect technology,embracing diffractive optics (binary and multi-level phasegratings), holographic space-variant elements andmicro-refractive optics.(3) Contributions on optical information processingarchitecture and demonstrator projects. The materials baseranges from silicon to II-VI materials with the realisationof pn-junction devices in ZnSe.The research reported here lays the basis for long-termprogress in devices for information processing.