The first part focuses on the major claims for the merits of the 'market' as an economic regulator made by conventional economists since the days of Adam Smith. The second part considers the arguments of those theorists and thinkers who have been sceptical of those conventional claims. The latter includes the following traditions: early nineteenth century 'anti-capitalist' political economy in England and France: 'populist' anti-capitalist economics in nineteenth century America and Russia; 'state socialist' and 'planned economy' theories (both Marxist and non-Marxist); twentieth century Keynesian and Sraffian critiques of orthodox economics; and contemporary environmentalist critiques of the market.