Résumé : Managerial practices are important drivers of firm productivity. In this paper, we focus on how firms manage knowledge exchanges across their different functions, a set of practices that we denote "Knowledge Integration" (KI), which has been shown to increase the productivity of R&D assets. We empirically analyze the drivers of KI adoption within firms and in particular how the adoption decision is affected by the threat of knowledge spillovers to competitors associated with these practices, controlling for different appropriability conditions. Using confidential survey data from 1,378 R&D labs of manufacturing firms in the United States, we estimate the probability of adoption of these practices as a function of firm- and market-level characteristics. We find that the intensity of (tacit) knowledge spillovers at the market level has a negative and significant impact on the likelihood that firms to adopt KI, with detrimental consequences for innovation and R&D performance.