This presentation introduces a psychosocial aftercare program specifically designed for intensive interdisciplinary pain treatment (IIPT). Although IIPT is a highly effective treatment for pediatric chronic pain, not all patients benefit sufficiently from the program. One core issue of the short but intensive treatment is the successful generalization of newly learned treatment content, such as an active daily structure and pain coping strategies, into everyday life. Support in this critical transition period after IIPT is crucial for long-lasting therapy success. Therefore, we developed a psychosocial aftercare program based on the well-established concept of case management, implemented by a trained social worker in close collaboration with a psychotherapist and pediatrician. The effectiveness of this new aftercare approach was examined in a multicenter randomized controlled study with N=419 patients who were followed for 12 months after discharge from IIPT. Additionally, a long-term follow-up was conducted 18-30 months after discharge to assess the intervention’s effectiveness during the COVID-19 pandemic. Data indicate a clear long-term superiority of the new aftercare program compared to aftercare as usual, even under pandemic conditions. Further, in a qualitative study with interviews of 16 persons involved in the original study (patients, parents, healthcare professionals), effectiveness mechanisms were identified.