Study Design. Retrospective review of a prospective cohortObjective. To determine the incidence and risk factors for 30-day morbidity and mortality following pediatric deformity spinal surgery.Summary of Background Data. Pediatric deformity spinal surgery is generally considered a safe and effective treatment option. The rising costs associated with spinal surgery and related peri-operative complications have received national attention. Few studies with standardized definitions and data collection methods exist.Methods. A large, multi-center clinical registry specifically designed to collect pediatric surgical outcomes was queried for all patients undergoing spinal deformity surgery in 2012. CPT codes were used to select patients undergoing anterior, posterior, and combined fusions. Detailed patient and case characteristics were analyzed. Thirty-day morbidity and mortality rates were calculated. Univariate and multivariate logistic regression analysis was used to identify patient characteristics, comorbidities, and operative variables predictive of complication.Results. In total, 2,005 pediatric patients undergoing deformity spinal fusion were included. The rate of 30-day complications was 10.0%; with a mortality rate of 0.15% (3 patients), a morbidity rate of 8.4%, reoperation rate of 3.74%, and readmission rate of 3.94%. Morbidity was highest in the Neuromuscular group (13.09%) and lowest in the Idiopathic cohort (5.69%), p < 0.01). Compared to posterior fusions, anterior fusions and those extending to the pelvis were associated with higher complication rates (p < 0.01). Risk factors for complication included hepatobiliary disease (p = 0.03), cognitive impairment (p = 0.02), elevated ASA Class (p<0.01), and prolonged operative time (p<0.01).Conclusion. The overall rate of 30-day morbidity after pediatric spinal deformity surgery was 10%. Multiple patient comorbidities and surgical duration and invasiveness were associated with an increased complication risk. This data may aid in the informed consent process, facilitate patient risk assessment, and allow quality comparisons between surgeons and institutions.