Leveraging external sources of knowledge has become a vital element of innovation strategy, especially in emerging markets, where many firms lack the sophisticated knowledge required to innovate. However, extant research in this domain puts little emphasis on emerging economies and also typically treats openness as a firm-level concept. In contrast, this study investigates how individual employees rely on both internal and external knowledge to increase their innovative work output (and, secondarily, their customer acquisition performance) and how their supervising manager’s characteristics moderate these mechanisms. Using hierarchical linear modeling of data collected from 123 employees and 50 managers in telecommunications companies in the emerging market of Vietnam, we find support for our hypothesized relationships. These findings have important implications for research and practice as they highlight the role of the individual employee in open innovation, the need for considering a more distributed set of organizational functions, and the relevance for emerging markets.