In the CPT project, VTT had two main tasks to lead. First task focused on advanced aftertreatment technologies and the second focused on variable valve actuation technologies and on studying the performance and potentiality of hydrogen fuelled internal combustion engines. Advanced aftertreatment technologies are needed to supplement the new combustion methodology in order to obtain the ultra-low emission levels. Experimental work, conducted at research facility developed by VTT, concentrated on aftertreatment devices to reach ultralow NOx and low particle emissions. All these aftertreatment and emission related experimental studies were closely linked to the company projects proving them valuable information needed in developing technologies to reduce emissions. Variable valve actuation (VVA) technologies, which were studied in the second task lead by VTT, are seen as enablers for achieving the ultra-low emissions. VVA technology enables exhaust gas aftertreatment system operation on optimum operation area allowing low emissions and reduces fuel consumption. Hydrogen combustion in off-road HD engine was studied at VTT as well. Hydrogen is one of the most interested fuel option for the future not only for usage in fuel cells but also in internal combustion engines (ICE). Hydrogen usage in ICE would allow the usage of current vehicle construction without major modifications as the engine itself by its characteristics is similar as current diesels. The hydrogen engine demo produced new relevant knowledge to be used in the companies’ own R&D activities.