The book addresses the charging of piston internal combustion engines. It discusses the charging devices and systems themselves, the theoretical relationships between the engine and charging systems, and finally the criteria for the interaction of this system combination, with particular emphasis on operational behavior. New insights into the development and adaptation of charging systems, new forms of representation, as well as the calculation and simulation methods currently used are presented, explained, and evaluated with examples. A focus is placed on the operational and control behavior of charged internal combustion engines in various application areas. A selection of application examples and a look at potential further developments of the "charging engine" system conclude the discussion.