Catastrophizing about pain has emerged as a critical variable in how we understand adjustment to pain in both adults and children. In children, however, current methods of measuring catastrophizing about pain rely on brief subscales of larger coping inventories. Therefore, we adapted the Pain Catastrophizing Scale (Sullivan et al., 1995) for use in children, and investigated its construct and predictive validity in two studies. Study 1 revealed that in a community sample (400 boys, 414 girls; age range between 8 years 9 months and 16 years 5 months) the Pain Catastrophizing Scale for Children (PCS-C) assesses the independent but strongly related dimensions of rumination, magnification and helplessness that are subsumed under the higher-order construct of pain catastrophizing. This three factor structure is invariant across age groups and gender. Study 2 revealed in a clinical sample of children with chronic or recurrent pain (23 girls, 20 boys; age range between 8 years 3 months and 16 years 6 months) that catastrophizing about pain had a unique contribution in predicting pain intensity beyond gender and age, and in predicting disability, beyond gender, age and pain intensity. The function of pain catastrophizing is discussed in terms of the facilitation of escape from pain, and of the communication of distress to significant others.