Cybernetics comes in two flavours: a more engineering flavour (first-order cybernetics); and the less known though in many ways older second-order cybernetics, relating more to the humanities, design and social sciences. This second-order cybernetics has been under-theorised in universities, and other research environments. Karl H. Müller's new book, his second volume on the New Science of Cybernetics, provides outstanding, general and innovative coverage that should enable scholars to bridge the gap between the work of second-order cyberneticians and others who work with similar approaches, and these institutions. It is an important book that can lead to significant insights, methods and actions. Ranulph Glanville, president of the American Society for Cybernetics (ASC), professor of architecture and cybernetics, University College London For Heinz von Foerster Vienna was a vital intellectual laboratory for cybernetic thinking in the past. I view the recent Viennese work on a new science of cybernetics by Karl H. Müller as an important Viennese contribution to widen and to deepen cybernetic research for the future. I hope that this book will become a stimulus for a renewed interest in the scope and in the potential of contemporary cybernetic thinking. Louis H. Kauffman, professor of mathematics, University of Illinois and past president of the American Society for Cybernetics (ASC) In recent years I have become increasingly interested in the notions of reflexivity and second-order cybernetics as examples of a reflexive science. In my view, Müller’s second volume of a new science of cybernetics offers an innovative and general approach to a new type of reflexive science. I hope that Müller’s New Science of Cybernetics will initiate a broad discussion leading to recreating cybernetics for the 21st century. Stuart A. Umpleby, professor of management, George Washington University and past president of the American Society for Cybernetics (ASC)