Manufacturing process optimization and cost control are the two main goals of engineersand technicians in charge of materials engineering. They must reconcile with precision thebest usage properties of parts with the right choice of thermal and surface treatments.But are they really aware of the potential of combined treatments, often called duplex,which are immensely promising, often unknown and yet can improve resistance toaggressive chemical, thermal and mechanical environments while also limiting costs?The objective of this European Conference is to take stock of the latest advances in thefield and discover the new possibilities offered thanks to the improved precision of thesetreatments, the progress of their modelling and the innovations contributed by the worldsof academic research and industry.In this context, combined treatments - both thermal and surface treatments - open up veryinteresting avenues to combat chemical, thermal and mechanical aggression while alsooptimizing costs.