Ideologies offers a fresh treatment of liberalism, conservatism, and socialism, as well as an examination of contemporary social movements such as feminism and environmentalism.

Professor Johnston treats each ideology as a product of the intersection of ideas and particular socio-historical contexts. Thus liberalism, conservatism, and socialism are discussed first in the context of the transition from feudal society to liberal modernity, and again as they have evolved within the shifting contexts provided by ascendant liberalism. In this way it is possible to distinguish the often diverse bodies of opinion that employ a common ideological label, and at the same time, sketch and emerging ideological consensus that frequently cuts across ideological lines.

Ideologies contains separate chapters on the liberal democratic consensus that has developed around conceptions of justice and democracy on the one hand, and the utility of the market economy on the other. Challenges to this twentieth century consensus from within the liberal democratic tradition are represented by anarchism, populism, feminism, and environmentalism. External challenges from currents of authoritarianism, nationalism, and fundamentalism are also discussed, along with ideologies once powerful but currently out of favour-fascism and Marxist-Leninism. In the final chapter, the strengths and weaknesses of ideology are judged, and its future prospects assessed.