The problems of both technical change and the regulation of the economic systems conjured up during the 1980s a series of considerations which may globally be centred around the issue of ‘structural changes’. This matter is at the heart of the evolutionist approaches which associate the process of structural change to the transition from a techno-economical paradigm to another (Freeman, 1988). It is also a central issue in the works of the regulationists for whom structural change is tied to the crisis of the Fordist regime and to the emergence of a new regulatory mode (Boyer, 1988) 1 . Among the most important illustrative factors of the process of structural change are innovation and technical progress. In the evolutionary theory perspective, the general economic evolution is governed by the nature of technology. If for the regulationist, the modification of the regime cannot be reduced to a purely technological aspect, it is nevertheless deeply present and it contributes to characterise the new ‘flexible production system’. For each of these approaches the question of structural change is therefore tied to the outbreak of a new technical system and of new forms of production.