Based upon Foucault's 1978 and 1979 lectures at the College de France on rationalities of government, this volume is a follow-up to Power/Knowledge which was published by Harvester Wheatsheaf in 1980. In these lectures Foucault examines the art or activity of government in its present form and within a historic perspective, and the different ways in which it has been made thinkable and practicable. This work on political discourse and governmentality is supplemented by chapters from nine international scholars. United by the common influence of Foucault's approach, they explore the many modern manifestations of government - the reason of state, police, liberalism, security, social economy, insurance, solidarisme, welfare, risk management and others. The book's theme is that the object and activity of government are not instinctive and natural things, but things that have been invented and learnt. The Foucault Effect analyzes the thought behind practices of government and argues that criticism represents a true force for change in attitudes and actions, and that extending the limits of some practices allows the invention of others.