Book excerpt: Combining original theoretical ideas and interpretation with ethnographic evidence, Johnson and Earle seek to describe and account for the development of complex human societies. A wealth of case studies are referred to throughout and these are used to support arguments for the proposed causes, mechanisms and patterns of change and for the factors involved, such as technological change, population growth, warfare, the exchange of goods. This second edition sees a complete re-writing of the theoretical chapters, taking account of recent research, plus a new chapter on changes since the Industrial Revolution and the globalisation of society.