Born in Vienna, Austria on December 24, 1950, Walter Steurer studied chemistry at the University of Vienna. After finishing his doctoral dissertation under the supervision of Prof. Hans Nowotny at the Institute of Physical Chemistry, he moved, in 1980, to the University of Munich, Germany, where he worked as a research assistant and lecturer. In 1987 he concluded his habilitation thesis in the field of crystallography and mineralogy. In 1990 he receive the Victor-Moritz-Goldschmid Award of the Deutsche Mineralogische Gesellschaft (DMG) for his contributions to the higher-dimensional structure analysis. His research topics were uncommon crystals and their phase transitions, and included incommensurably modulated structures, quasicrystals and polytypes. For a short period, from 1992 until 1993, he was professor of crystallography at the University of Hanover, Germany. After rejecting calls to the Universities of Hamburg and Munich, Germany, he has been full professor of crystallography at the Laboratory of Crystallography of the ETH and University of Zurich since the fall of 1993. In 2008, Walter Steurer received the Jean Marie Dubois Award for Excellence in Quasicrystal Research. At present, his research topics comprise structural studies of aperiodic crystals and their phase transformations, the modeling of order/disorder phenomena, and higher-dimensional crystallography. Sofia Deloudi, was born in Athens, Greece on March 27, 1980. She studied interdisciplinary natural sciences at the ETH Zurich and concluded her doctoral dissertation under the supervision of Prof. Walter Steurer at the Laboratory of Crystallography of the ETH. At present, she is a junior scientist with her focus on modeling of quasiperiodic structures and higher-dimensional crystallography.