Preliminary data are presented characterizing Union Carbide Corporations Thornel 50, the Royal Aircraft Establishments RAE, and H.I. Thompson Companys graphite fiber reinforcements in plastic matrix composites. Single filament properties as well as the physical and mechanical properties of composites are presented. Fabrication of woven graphite fiber fabric and braided fiber composites are included. Long term humid aging effects on composite flexural and shear properties are presented. The specific properties of composites fabricated with graphite reinforcements available at the time of writing are compared to previously characterized advanced composite systems utilizing such reinforcing filaments as S-glass, Boron, and other graphites. Author.