Phil Ball’s little book is one of the best summaries I have come across on complexity theory and its applications. This little triumph of clarity argues that society’s problems are those of highly connected systems. The book has been written to support the FuturICT project which seeks to convince that a new interdisciplinary synthesis – a new social physics if you like – is required to unravel such problems of this complexity. Phil says of contemporary social problems “… the consequences … are immense, and yet at this stage are little more than informed guesswork” (page vii). Nice gentle text. If are a newcomer to complexity sciences, then read this first. Lots of references to our own work in CASA here on cities, and to friends of CASA such as Paul Ormerod, Bill Hillier and others.