Any explanation of political collapse carries lessons not just for the study of ancient societies but for the members of all complex societies in both the present & future. Dr Tainter describes nearly two dozen cases of collapse & reviews more than 2000 years of explanations. He then develops a new & far-reaching theory that accounts for collapse among diverse kinds of societies evaluating his model & clarifying the processes of disintegration by detailed studies of the Roman Mayan & Chacoan collapses.