The United States is focusing on three key transportation issues: air quality, fuel economy, and alternative fuels. Policies include stricter vehicle emissions standards, using alternative fuels like alcohols, and restricting driving in polluted areas. Some cities already require oxygenated gas blends, and California has vehicles running on methanol. Fuel efficiency laws were set in the late 1970s, aiming for 32 mpg by 1995. Research is ongoing for a national system where vehicles can switch between gasoline and alternative fuels.