In the first part of this book the various basic heat transfer processes are considered, -- simple convective heat transfer from hot gases to the engine walls under various conditions, radiation heat transfer, and coolant heat transfer processes. This part is followed by one describing the various methods of cooling used in liquid propellant rocket engines, such as regenerative, film, ablation and radiation cooling. The final part concerns the properties of materials that will have to be known by the engine designer, from the transport properties of the hot combustion gases to those of the materials from which the engine will be constructed. Emphasis was placed on presenting simple methods for calculating the magnitude of heat transfer rather than providing the most modern and rigorous theories, particularly in the field of developing boundary layers. (Author).