Composites are the fastest growing class of structural material. Consequently, electronic properties are often difficult to find. This report was prepared in order to present a compilation of reliable data on the electronic and electrical properties of composites. Composites provide an opportunity to tailor the properties to the application; a factor that allows designers an unlimited variety of new materials for new uses. It is this feature that has contributed to the rapid growth of composites. The electrical properties of a composite can be of vital importance in the use or application of the material in a system. The designer therefore, must be able to obtain the necessary electrical or electronic property data to guide him in the materials selection. It is the purpose of this report to assist the designer and engineer in fulfilling that requirement. Properties This report provides a compilation of the most commonly required electronic properties data of structural composites. Thermal properties often influence electrical design; consequently several of these properties are included. The specific properties tabulated are: Arc Resistance Thermal Conductivity Arc Tracking Resistance Linear Thermal Expansion Dielectric Constant Coefficient Dissipation Factor Electrical (Volume) Resistivity Electrical (Volume) Conductivity Other electrical and thermal properties are compiled as the data was made available.