According to the metacognitive theory of psychological disorder, metacognitions are vulnerability factors in predicting development of psychological symptoms. The present study investigated metacognitive factors and life stress in a prospective test of their proposed temporal precedence in the development of anxiety and depression symptoms. Participants were 172 students and adults recruited in Ankara and Bolu, Turkey. Two separate sets of hierarchical regression analyses were conducted. In these analyses, Time 2 anxiety or depression was regressed on the main and interaction effects of metacognition and stress after controlling for baseline symptom levels measured at Time 1, age, and gender. Results revealed that negative metacognitive beliefs about the uncontrollability and danger of worry significantly predicted residual change in both anxiety and depression after controlling for the negative effect of stressful life events. Furthermore, lack of cognitive confidence interacted with daily hassles to predict the change in anxiety, when the baseline level of anxiety and other individual differences were controlled. Our results support the metacognitive theory of psychopathology. (C) 2010 Elsevier Ltd. All rights reserved.