Communicating Process Architectures 2008 contains the proceedings of the thirty-first Communicating Process Architectures Conference (CPA 2008) organized under the auspices of WoTUG and the Department of Computer Science of the University of York. The aim of this book is to cover both theoretical aspects and industrial applications of Communicating Processes. Two invited speakers have given excellent contributions to this topic. Professor Samson Abramsky has worked in the areas of semantics and logic of computation, and concurrency. His work on game semantics considers interaction and informat.