This study establishes a theoretical and integrative framework for analyzing the relationship between knowledge hiding and task performance. The existing literature indicates that knowledge hiding is prominent in service sector firms and impedes knowledge transfer. However, the potential determinants and consequences have not been extensively investigated. The objectives of this study are threefold: First, examining the effect of distrust and the complexity of knowledge on knowledge hiding. Second, examining the effect of knowledge hiding on task performance. Third, examining the conditional effect of task relatedness in the relationship between distrust, knowledge complexity, and knowledge hiding. We conducted an online survey by using a Google form to collect our data. We gathered data from 325 salespersons in the business departments of a single firm in Indonesia. To test our hypotheses, we employed Partial Least Square (PLS). The results revealed that distrust and knowledge complexity are critical factors in predicting knowledge hiding. Interestingly, knowledge hiding positively affects task performance. The rationale behind this result is that employees tend to believe that hiding knowledge is a strategy to boost their performance in the short run. The contribution of this study is the suggestion that organizations should implement a knowledge-sharing culture to minimize knowledge hiding.