The Prius Hybrid Electric Vehicle (HEV) represented approximately a billion dollar investment by Toyota to develop a compact car rated at 41 MPG. The program began in 1993 with initial Japan shipments in late 1997 and first shipments in the U.S. in late 2000. The MPG rating was about twice the average MPG of an equivalent 2000 car in the U.S. The research and development (R&D) budget for the automobile industry is over $100 billion dollars annually. For about 1 percent of one year’s R&D, an innovative major improvement was made in gasoline engine efficiency. There have been other billion-dollar efforts in the past that have resulted in little or no difference in MPG, including the diesel hybrids of the U.S. PNGV program, fuel cell cars, and the BEVs of the Californian Air Resources Board (CARB) era of the late 1990s. The gasoline HEV represents the most significant technological improvement in fuel economy achieved in the last three decades.