Nowadays, human-object and human-human interactions are often facilitated by computational means. Interaction designers aim at designing such interactions to make them more effective and pleasant. Sonic Interaction Design emphasizes the role of sound as a mediator of meaningful interactions. A COST Action on Sonic Interaction Design was run between 2007 and 2011, to pro-actively contribute to the creation and consolidation of new design theories, tools, and practices in this innovative and interdisciplinary domain. The Action stood on four legs: cognitive science, design, interactive art, and information display. This book reports on many research activities that have been conducted over a four-year period, organized as workshops, training schools, short-term scientific missions, and an exhibition. Davide Rocchesso is associate professor at the IUAV University of Venice, Italy.