Guillaume F. Nataf completed his joint PhD in 2016 at the University Paris-Saclay (France) and the University of Luxembourg. In 2017 he moved to the University of Cambridge as postdoc and obtained a Research Fellowship from the Royal Commission for the Exhibition of 1851. In 2021 he became a CNRS Research Scientist at the GREMAN laboratory, Tours, France. A year later he was awarded an ERC Starting Grant to investigate thermal transport in ferroelectric and ferroelastic materials. Ekhard K.H. Salje completed his PhD at Hannover University, Germany, in 1972 and became Head of the Institute for Crystallography and Petrology (Hannover University) in 1983. In 1985 he moved to the University of Cambridge where he became Professor of Mineral Physics (Department of Earth Sciences) in 1992. He published several key articles on ferroelastic materials, including the first publication on domain boundary engineering, which highlighted that domain walls can be used as functional interfaces. Blai Casals is an Assistant Professor of Physics at the University of Barcelona, Spain. He obtained his PhD from the Universitat Autònoma de Barcelona in 2018. As a postdoctoral researcher he spent 2.5 years at the University of Cambridge and two years as a postdoc at the Catalan Institute of Nanoscience and Nanotechnology (ICN2).