The thermal protection system (TPS) of a space vehicle ensures the structural integrity of the surface of the craft and maintains the correct internal temperatures (for crew, electronic equipment, etc.) when the vehicle is under the severe thermal loads of re-entry. These loads are characterised by very large heat fluxes over the relatively short period of re-entry. The design of thermal protection systems for re-entry vehicles is very complex due to the number and complexity of phenomena involved: the flow around the vehicle is hypersonic, tridimensional and reactive, and its interaction with the vehicle s surface may induce chemical reactions which are not fully understood. Two TPS concepts for re-entry vehicles, ablative and radiative are examined and there is also an anlyisis of existing systems using them. The Thermal design handbook is published in 16 Parts TR 17603-31-01 Thermal design handbook Part 1: View factors TR 17603-31-02 Thermal design handbook Part 2: Holes, Grooves and Cavities TR 17603-31-03 Thermal design handbook Part 3: Spacecraft Surface Temperature TR 17603-31-04 Thermal design handbook Part 4: Conductive Heat Transfer TR 17603-31-05 Thermal design handbook Part 5: Structural Materials: Metallic and Composite TR 17603-31-06 Thermal design handbook Part 6: Thermal Control Surfaces TR 17603-31-07 Thermal design handbook Part 7: Insulations TR 17603-31-08 Thermal design handbook Part 8: Heat Pipes TR 17603-31-09 Thermal design handbook Part 9: Radiators TR 17603-31-10 Thermal design handbook Part 10: Phase Change Capacitors TR 17603-31-11 Thermal design handbook Part 11: Electrical Heating TR 17603-31-12 Thermal design handbook Part 12: Louvers TR 17603-31-13 Thermal design handbook Part 13: Fluid Loops TR 17603-31-14 Thermal design handbook Part 14: Cryogenic Cooling TR 17603-31-15 Thermal design handbook Part 15: Existing Satellites TR 17603-31-16 Thermal design handbook Part 16: Thermal Protection System