Most objections to state intervention in social life are made on overtly political or moral grounds. Originally published in 1980, the theme of this book is similarly to criticise intervention programmes, but on fundamentally empirical grounds. Rather than investigate the extent of the ignorance in social intervention, it chooses to look at several forms of intervention – Field Social Work, Youth Work, School Health Education, The Manpower Services Commission, the Social Science Research Council and Community Health, and discusses the types and variety of ignorance which aspects of these display. It is demonstrated that the failure of social intervention is due to the defective nature of the knowledge ‘bases’ of such intervention sociology. The book investigates the suspicion that those who research, enact and implement social change policies in any of the above-mentioned fields, do not really know what they are doing. Of course there is no necessity that intervention is so ill-informed. Yet an awareness of the reasons for the inadequacies of past interventions must be gained if future failures are to be avoided.