Smiths analysis of the relationship between division of labour and the wealth of nations interpreted as per capita income is illustrated, through their connection with productivity. The division of labour also explains the existence and characteristics of social stratification and alienation. The classical tripartition in social classes – capitalists, landlords and workers – is discussed, considering both its explanatory value and its limits. Division of labour evolves through time: Babbages laws, Taylorism, the production chain, mechanization. The international division of labour and international value chains are considered. Marxs communist utopia with the disappearance of compulsory labour is recalled and confronted with less unrealistic utopias concerning the command structure within the firm or Ernesto Rossis labour army.