Knowledge hiding prevents colleagues from generating creative ideas, but it may also have negative consequences for the creativity of the knowledge hider. Drawing on social exchange theory, we propose that when employees hide knowledge, they trigger a reciprocal distrust loop in which coworkers are unwilling to share knowledge with them. We further suggest that these effects are contingent on the motivational climate such that the negative effects of hiding knowledge on one's own creativity are enhanced in a performance climate and attenuated in a mastery climate. A field study of 240 employees, nested into 34 groups, revealed a negative relationship between knowledge hiding and the knowledge hider's creativity as well as the moderating role of a mastery climate. Study 2 replicated these findings in an experimental study of 132 undergraduate students, testing a reciprocal distrust loop and comparing it with an alternative intra-psychic explanatory process based on situational regulatory focus. Implications for practice and future research are discussed.