First published in 1976. Ideology plays an important role in many fields of human activity and has therefore been dealt with directly and indirectly in a vast number of studies, but a generally accepted definition of the term is lacking even in the various branches of social and political science. This book - the first since Mannheim to elaborate a comprehensive theory of ideology - seeks to offer a generally applicable definition, a task which of necessity involves taking issue with the logical and political implications of the conceptions in current use and which touches on central problems of politics and political science. Professor Seliger's theory is based on an approach and conceptualizations which will appeal both to ’traditionalists’ and 'behaviourists' since he gives due weight to both kinds of literature. Indeed, this book reflects throughout a detachment and independence of thought which are refreshing and opens up the way for both theorists and practising politicians to re-examine ideological tenets in the light of actual and feasible policy orientations and embark upon ideological reconstruction.