The history of the creation of gas-turbine units (GTU) is briefly stated. The first power-generating gas turbine was built by the Swiss company Brown Boveri in 1939. The efficiency of this gas turbine was 17.5%. The modern technical level of gas turbines is analyzed by the example of the most powerful of them (550–600 MW), produced by the four world power engineering firms: General Electric (United States), Siemens (Germany), Mitsubishi (Japan), and Ansaldo (Italy, Brown Boveri successor). The efficiency of such gas-turbine units has reached 44%, and combined-cycle gas turbines based on them have reached 63–64%. Their high efficiency is the result of the consistent development of science and technology: aerodynamics of turbomachines, high-temperature materials and designs of parts made of them with advanced cooling systems and new coatings, methods of forming such parts, and devices for low-emission combustion of fuels and control systems. The prospects for the development of gas-turbine engineering in the world are considered. The dependence of the unit cost of various types of gas turbines on their capacity is given. It is concluded that the use of the most powerful and economical gas turbines in the domestic electric power industry will allow for the reduction in fuel consumption for electricity generation by more than a third. The creation of the most advanced gas-turbine units in the country using the experience of domestic aviation gas turbine construction is necessary for the technical reequipment of the Russian electric power industry.