OBJECTIVES AND DESIGN. Rumination (specifically Brooding) is thought to be an important vulnerability factor for depressive symptoms whereas Worry is believed to be involved in anxiety. The present study sought to clarify the extent to which these two types of perseverative cognition show symptom specificity or generality in their associations with depression and anxiety. Additionally, reactive (negative affectivity, NA; positive affectivity, PA) and self-regulatory aspects of temperament (effortful control) were considered as vulnerability factors for depression and anxiety and were also studied in relation to rumination and worry. METHODS. Self-report questionnaires tapping Rumination, Worry, temperament, depression, and anxiety were administered to a community sample of 138 children aged 9-13. RESULTS. Brooding (but not Reflection) and Worry were significantly associated with anxiety and depressive symptoms on the one hand and with the temperamental construct of NA on the other hand. However, consistent with a model predicting symptom-specific relations, only Brooding significantly mediated the association between NA and depressive symptoms, whereas only Worry was a mediator of the relation between NA and anxiety symptoms. Finally, among self-regulatory aspects of temperament, activation control and inhibitory control were uniquely associated with depressive symptoms, whereas attentional control was only associated with anxiety symptoms. CONCLUSIONS. This study supports high NA as a vulnerability factor for the development of depressed and anxious symptoms in children, but these symptoms develop through differential paths.