This article is based on empirical research carried out in two engineering firms in England. In the course of the 1970s these firms reorganised labour relations at workplace level; the changes observed were fairly consistent with the general trend in manufacturing industry in that country. The purpose of the research was to determine how this institutional reform affected the control exercised by production workers over the organization and execution of their work.

Observation and interviews with participants show that, underneath comparable organizational and institutional features, fundamentally different social relations have developed and, despite the reform, persisted. After drawing attention to this contrast in the nature and degree of control exercised by manual workers, the article goes on to analyse the foundations of this pattern of job control. The focus is on the technical conditions of production observed and the interaction of technical with social factors. In particular, at the factory where workers' organization was most articulate, the organization of shop stewards had developed in keeping with the technical division of labour.

The first part of the article explains the field of study, the research method and the main characteristics of the firms observed. The second section surveys the scope and degree of job control in 1979-1980, after the institutional reform and in a context of economic decline. In a third part, attention turns to the interaction between technical and social factors which may explain the emergence and consolidation of the pattern of social regulation observed in these production units. In conclusion, stress is laid on some possible implications of this research for theory and for policies of labour relations reform, and the results obtained are viewed in relation to some recent trends in Great Britain.