This volume contains papers presented at the 1996 MRS Spring Meeting during the symposium on III-Nitride, SiC and Diamond Materials for Electronic Devices. The meeting was held in San Francisco. California, from April 8-12. The symposium involved over 140 papers that included invited presentations and contributed oral, poster and late news posters, as well as a panel discussion held mid-week. This symposium differed from several previous MRS symposia on wide bandgap semiconductors in that the emphasis was specifically on materials aspects related to electronic properties and devices. The proceedings volume is organized much as the meeting, but with poster and oral presentations mixed according to the session topics. Solid advances were reported in the growth techniques of all three materials groups. Contributions demonstrated the critical importance of surfaces, interfaces, doping, defects, and impurities. Reports showed potential device applications ranging from new high-frequency, high-power all solid-state devices to unique cold cathode electronic devices. While the results presented here demonstrate real promise for a wide range of new solid-state devices that are not feasible with current production materials, substantial progress in materials research is necessary to fulfill the real potential of these applications. A lively panel discussion was held in the middle of the conference which focused on several critical issues related to the electronic potential of the three materials.