The transport sector continues to shift towards alternative powertrains, particularly with the UK Government's focus on ending the sale of petrol and diesel passenger cars by 2030 and increasing support for alternatives. Despite this announcement, the internal combustion could continue to play a significant role both in the passenger car market through the use of hybrids and sustainable low carbon fuels including hydrogen, as well as a key role in other sectors such as heavy-duty vehicles and off-highway applications across the globe. The contributions presented at the International Conference on Powertrain Systems for a Sustainable Future 2023 (London, UK, 29- 30 November 2023) focus on the internal combustion engine's role in net-zero transport as well as covering developments in the wide range of propulsion systems available (electric, hydrogen internal combustion engines and fuel cells, sustainable fuels etc) and their associated powertrains. To achieve a sustainable future for transport across the globe we will need to deploy all technologies and so, to help understand how these might fit together, life-cycle analysis of future powertrain systems and energy will also be included. Powertrain Systems for a Sustainable Future provides a forum for engine, fuels, e-machine, fuel cell and powertrain experts to look closely at developments in powertrain technology required to meet the demands of the net-zero future and global competition in all sectors of the road transportation, off-highway, marine and stationary power industries.