The purpose of this study is to examine the effect of a firm's ability to integrate knowledge on their innovation performance, in order to help firm's prioritise their resources, used for knowledge integration, more effectively. Data were collected from a survey mailed to R&D managers in firms with between 100–1,000 employees in a cross-section of industries. Five hypotheses were tested using multiple regression analysis with and without interaction terms. The results indicate that a categorisation of knowledge is useful for understanding knowledge integration. The study also shows that the ability to integrate domain-specific knowledge is significantly related to innovation performance. Furthermore, the results indicate that technology turbulence in the industry has a positive moderating effect on the above relation. Managerial implications suggest how managers can focus their efforts in order to effectively integrate knowledge in product development projects.