Over the last decade，the high speed direct injection(HSDI)diesel engine has made dramatic progress in both its performance and market share in the light duty vehicle market. However，with ever more stringent emission legislation to be introduced over coming years，the simultaneous reduction of NOx and Particulate Matter(PM)from the HSDI diesel engine is being intensively researched. As part of a European Union(EU)NICE integrated project，research has been carried out to investigate the fuel injection and combustion from a narrow cone fuel injector in a high speed direct injection single cylinder engine with optical access utilising a multiple injection strategy and various alternate fuels. The fuel injection process was visualised using a high speed imaging system comprising a copper vapour laser and a high speed video camera. The autoignition and combustion process was analysed through the chemiluminescence images of CHO and OH using an intensified CCD camera. The combustion temperature and soot loading distributions were measured using the two-colour method.