Advanced thermal protection materials envisioned for use on future hypersonic vehicles will likely be subjected to temperatures in excess of 1811 K (2800 F) and, therefore, will require the rapid conduction of heat away from the stagnation regions of wing leading edges, the nose cap area, and from engine inlet and exhaust areas. Carbon-carbon composite materials are candidates for use in advanced thermal protection systems. For design purposes, high temperature thermophysical property data are required, but a search of the literature found little thermal conductivity data for carbon-carbon materials above 1255 K (1800 F). Because a need was recognized for in-plane and through-the-thickness thermal conductivity data for carbon-carbon composite materials over a wide temperature range, Langley Research Center (LaRC) embarked on an effort to compile a consistent set of thermal conductivity values from room temperature to 1922 K (3000 F) for carbon-carbon composite materials on hand at LaRC for which the precursor materials and thermal processing history were known. This report documents the thermal conductivity data generated for these materials. In-plane thermal conductivity values range from 10 to 233 W/m-K, whereas through-the-thickness values range from 2 to 21 W/m-K. Ohlhorst, Craig W. and Vaughn, Wallace L. and Ransone, Philip O. and Tsou, Hwa-Tsu Langley Research Center...