In this study, we investigate idea generation by conducting a diary study. We hypothesized that idea generation depends on problem identification, and that this relation is moderated by two factors: (a) the number of social interactions an individual has with "non-redundant" network connections, and (b) an individual's level of vigor. The hypotheses were tested by making use of a diary study among 31 employees of a Dutch applied university over a period of 2 weeks. Results showed that idea generation results from the identification of problems that require new ideas to solve them. An individual's number of social interactions and the level of redundancy of these social interactions moderated this relation. The level of vigor of an individual did not predict idea generation, but results suggest that vigor is needed for interacting with others. Furthermore, this study contributes to the creativity research using a new approach to look at the effects of social interactions by relating them to the overall structure of social networks.