Objective: To synthesize and critically evaluate evidence on the effectiveness of integrated psychological care models for children with complex chronic illness within pediatric hospital settings and provide recommendations for successful implementation. Design: Six electronic databases (Medline, Cochrane, Embase, PsycINFO, Scopus, CINAHL) were systematically searched for English language studies including families of children aged 0-17 years with complex chronic illness. Eligible studies reported on psychology or neuropsychology screening, assessment, intervention, or services provided within a pediatric hospital setting. Results: Fifteen studies were identified for review; nine assessed a psychological service, five examined psychosocial screening, and one examined a neuropsychology service. Three studies demonstrated the effectiveness of integrated psychological services in improving child or parent physical, psychological, or behavioral health outcomes. Uptake of psychosocial screening was high (84-96%), but only 25-37% of children or families identified as 'at-risk' engaged with on-site psychology services. Integrated psychological services offering consultations at the same time and location as the child's medical visit reported the highest rates of uptake (77-100%). Conclusions: The available evidence supports co-location of child medical and psychological services. A more consistent and comprehensive approach to the assessment of patient- and caregiver-reported outcomes and implementation effectiveness is recommended.