This paper presents new evidence on the practice of industrial Research and Development (R&D), especially its allocation between learning and internal research, and the role of outside knowledge in reshaping this allocation. The evidence describes the sources of outside knowledge, portrays the flow of that knowledge into firms, and interprets the channels by which outside knowledge influences R&D. In this way, the paper illustrates R&D's value in dealing with disequilibria. The empirical work is based on a sample of 220 R&D laboratories owned by 115 firms in the US chemical, machinery, electrical equipment, and motor vehicle industries. The findings are consistent with the view that universities and firms generate technological opportunities in R&D laboratories. In addition to partnerships that define rather strict channels of opportunity, the paper uncovers broader effects of R&D spillovers. The results also suggest that academic spillovers drive learning about universities and that industrial spillovers drive learning about industries. Thus, externally derived opportunities reshape the rate and direction of R&D. Overall the findings paint an image of practitioners of industrial R&D reaching aggressively for opportunities rather than waiting for opportunities to come to them.