In recent years, substantial advances have been made in understanding the coupling between chemical and biological processes and mechanical and hydraulic behaviours in soils and rocks. At the same time, experimentation and modelling capabilities have progressed significantly, allowing effective design of geotechnical applications. The need for such analyses arises, for example, in chemical and biological soil improvement; nuclear, hazardous and municipal waste containment; petroleum and natural gas extraction; methane hydrate exploitation; CO2 sequestration; and assessment of pavement durability. The seventeenth Géotechnique Symposium in Print took place at the Institution of Civil Engineers on 3 June 2013 and sought to address the new challenges that are emerging from the interactions between multi-physical phenomena. These proceedings bring together the international research presented at the symposium and published across two issues of Géotechnique as well as additional subsequent research published in the journal.