According to the recent discussion on the relationship between sociology and economics, labour market is an interesting and peculiar field: trespassing from one discipline to the other has been more frequent then in other fields. In this review we adress two questions: a) why is labour market a peculiar area, with many exchanges between sociologists and economists?; b) what are the specific contributions given by the sociologists to this field? We propose an analytical distinction of sociological and economic theories according to the object and level of the analysis. In this way we identify three groups of theories: the first one studies the individual outcomes on the labour market; the second focuses on the organization of work in the firm; the third studies the norms that regulate work at the overall level of the labour market and at the individual level.