Much of the credit for 20th-century advances in computing and communication goes to the silicon transistor and the integrated circuit. The same may be said for the silicon insulated gate bipolar transistor (IGBT) with respect to the impending revolution taking place in energy technology. The silicon IGBT offers unprecedented energy efficiency when switching electrical power in the range of few hundred kilowatts to multimegawatts at a low manufacturing cost. It is transforming the electric utility, transportation, telecommunication, manufacturing, and medical infrastructures in a manner never seen before. This article pertains to the discovery and demonstration of early IGBT devices.