Through interviews and a large-scale survey of R&D scientists and engineers, this paper explores individuals’ attempts to absorb external knowledge, focusing on their efforts to identify and assimilate external knowledge and promote its utilization. Extant research does not explicitly address whether individuals should better specialize in certain absorption efforts or rather work as generalists dedicated to a range of efforts. We suggest that assimilation efforts increase the value of individuals’ efforts at external search and at promoting the utilization of external knowledge, which culminates in two main absorption roles that can help individuals achieve greater innovation performance. We argue that gatekeepers who combine external search with assimilation effort help to achieve innovation by contributing to building potential absorptive capacity, while shepherds who combine assimilation with utilization effort aid innovation by building realized absorptive capacity. We find support for these predictions and discuss the implications for research and managerial practice in open innovation.