An engine system and a method of controlling a combustion process in an internal combustion engine are disclosed. The combustion process is based on compression ignition of a stratified air-fuel mixture using a high octane fuel such as gasoline. Multiple fuel injections may be used in a given combustion cycle. Fuel injection timing, EGR, exhaust rebreathing, late intake valve closing, and intake boost are controlled to enable autoignition over essentially the entire speed and load operating range of the engine, while providing reduced emissions, low noise, and low fuel consumption.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under Contract No. DE-EE0003258 awarded by the Department of Energy. The government has certain rights in the invention.