This book is one of the early landmarks, still few in number, in the growth of a definitive theory of concurrent processes. Hennessy obtains a rich theory by marrying the observational view of processes with continuous algebra.
Robin Milner, University of Edinburgh, Department of Computer Science
A clear and scholarly account of pioneering research by the author and his colleagues into the relation between algebra and concurrency, two areas of the greatest current interest to practitioners of computing science.
Tony Hoare, Professor of computation, Oxford University