The Ilijan Plant is an advanced combined cycle power plant, the largest in the Philippines, with a rated capacity of 1,251 MW. The plant uses the latest G type gas turbines of Mitsubishi Heavy Industries, Ltd. (MHI), and the thermal efficiency of the plant is the highest in the world. In addition to the steam-cooled combustor system, unique to G type gas turbines, this plant introduced two more new features for the first time, namely dual firing on G type gas turbines and fuel gas heating system with boiler feed water. This article gives an outline of the Ilijan Plant and also describes the pioneering technology demonstrated and established at this plant.