Multinational corporations claim that their synergistic innovative capabilities—their ability to create and deploy innovations rapidly and successfully—have been enhanced by global R&D. But have they? In attempting to answer this question, the authors seemlessly integrate rigorous quantitative analysis—e.g., multivariate regression, factor analysis, and partial least squares analysis—with qualitative analysis of data from interviews and surveys.The data are provided by senior R&D executives in approximately 80 global R&D facilities from leading North American, European, and Japanese multinational corporations. In analyzing this wealth of information, the authors cover the role of slack resources, knowledge management processes, and top management team diversity, all in the context of global R&D and its impact on the synergistic innovative capabilities of multinationals.