Combustion synthesis is used to synthesize useful materials via combustion reactions. Compared to many other material synthesis approaches, combustion synthesis is furnace‐free and more efficient, with negligible energy consumption, short processing times, large productivities, and low costs of production. The unique conditions of combustion synthesis, characterized by extremely high temperatures and rapid heating/cooling rates, offers tremendous possibilities for controlling the microstructure and synthesis of novel materials. To date, combustion synthesis has been used to produce a wide variety of inorganic materials, including metals, ceramics, and metal–ceramic composites, in different forms of powders, coatings, and bulks. Today, combustion synthesis is associated with many scientific disciplines, is applied to various industrial fields, and represents a promising branch of modern science and technology with an ever‐growing influence. In this chapter, a comprehensive introduction to combustion synthesis, from theory to practice, is provided. Initially, some basic concepts and fundamentals of the process are elucidated, with the essential parameters of combustion reactions, including adiabatic temperature, propagation velocity and stability of combustion wave, being explained based on homogeneous models. Heterogeneous and discrete combustion models are then described for heterogeneous reaction media. Finally, the reaction mechanism of combustion synthesis is discussed, along with improvements in experimental skills. The processing of combustion synthesis (and materials thus created) are also reviewed. The effects of the main parameters in routine processing of combustion synthesis are discussed for solid–solid and solid–gas reactions. Details of various hybrid processes based on combustion synthesis are then presented, with high‐gravity combustion synthesis as a particular example. Finally, solution combustion synthesis and gas combustion synthesis are introduced, with emphasis placed on the preparation of nanosized particles.