Based on the emergence of a new technology as a starting point, this thesis deals with the capacity of industrial actors to reorganise their knowledge bases. In that purpose, we study knowledge integration processes dened as the search for technological complementarity in the knowlegde bases of actors engaged in innovation activities. In a given technological environment, the search for technological complementarity signifies the search for the most productive technological combinations. Our analysis is based on two dimensions: the intra-organisational knowledge integration processes and the inter-organisational knowledge integration processes. Applied to the case of the biotechnology and pharmaceutical industry, the econometric research - based on innovations, patents and alliances databases - conducted in this thesis allows us to draw two main results. Regarding the intra-organisational knowledge integration processes, we emphasize that the search for technological complementarity is determined by the stock offundamental knowledge that promotes the firrm's capacity to combine knowledge and hence, its capacity to innovate. Regarding the inter-organisational knowledge integration processes, we show that the search for technological complementarity determines the choice given to actors of one industry to form a strategic alliance, and that this search for technological complementarity evolves throughout the technological life cycle.
