Organic semiconductors enable the fabrication of large-scale printed and mechanically flexible electronic applications, and have already successfully established themselves on the market for displays in the form of organic light-emitting diodes (OLEDs). In order to break into further market segments, however, improvements in performance are still needed. Doping is the answer. In semiconductor technology, doping refers to the targeted introduction of impurities (also called dopants) into the semiconductor material of an integrated circuit. These dopants function as intentional "disturbances" in the semiconductor that can be used to specifically control the behaviour of the charge carriers and thus the electrical conductivity of the original material. Even the smallest amounts of these can have a very strong influence on electrical conductivity. Molecular. doping is an integral part of the majority of commercial organic electronics applications. Until now, however, an insufficient fundamental physical understanding of the transport mechanisms of charges in doped organic semiconductors has prevented a further increase in conductivity to match the best inorganic semiconductors such as silicon.