Knowledge-in-Use, i.e., the ability to apply what one has learned, is a major goal of education and involves the ability to transfer one's knowledge. While some general principles of knowledge transfer have been revealed, the literature is full of inconclusive results and it remains hard to predict successful transfer. However, research into expertise suggests that how one organizes one's knowledge is critical for successful transfer. Drawing on data from a larger study on the learning of energy, we employed network analysis to investigate how the organization of students' knowledge about energy influenced their ability to transfer and what role achievement goal orientation may have played in this. We found that students that had more coherently organized knowledge networks were more successful in transfer. Furthermore, we also found a connection between mastery goal orientation and the organization of students' knowledge networks. Our results extend the literature by providing evidence for a direct connection between the organization of students' knowledge networks, their success in transfer, and their goal orientation and hint at the complexities in the relationship between mastery approach goal orientation and successful transfer beyond what is reported in the literature.