The geotechnical construction industry is a major component of the overall construction sector and is strategically important in infrastructure development (transportation, flood and landslide protection, building foundations, waste disposal). Although industry and research in the overall construction sector have been investing significantly in recent years to produce innovative low-carbon technologies, little innovation has been created in geotechnical construction industry, which is lagging behind other construction industry sectors. This paper discusses the interplay between low-carbon geotechnical engineering and unsaturated soil mechanics based on the research carried out within the project TERRE (Marie Skłodowska-Curie Innovative Training Networks funded by the European Commission, 2015-2019,H2020-MSCA-ITN-2015-675762).