OBJECT The object of this study was to examine how procedural volume and patient demographics impact complication rates and value of care in those who underwent biopsy or craniotomy for supratentorial primary brain tumors. METHODS The authors conducted a retrospective cohort study using data from the Nationwide Inpatient Sample (NIS) on 62,514 admissions for biopsy or resection of supratentorial primary brain tumors for the period from 2000 to 2009. The main outcome measures were in-hospital mortality, routine discharge proportion, length of hospital stay, and perioperative complications. Associations between these outcomes and hospital or surgeon case volumes were examined in logistic regression models stratified across patient characteristics to control for presentation of disease and comorbid risk factors. The authors further computed value of care, defined as the ratio of functional outcome to hospital charges. RESULTS High-case-volume surgeons and hospitals had superior outcomes. After adjusting for patient characteristics, high-volume surgeon correlated with reduced complication rates (OR 0.91, p=0.04) and lower in-hospital mortality (OR 0.43, p<0.0001). High-volume hospitals were associated with reduced in-hospital mortality (OR 0.76, p=0.003), higher routine discharge proportion (OR 1.29, p<0.0001), and lower complication rates (OR 0.93, p=0.04). Patients treated by high-volume surgeons were less likely to experience postoperative hematoma, hydrocephalus, or wound complications. Patients treated at high-volume hospitals were less likely to experience mechanical ventilation, pulmonary complications, or infectious complications. Worse outcomes tended to occur in African American and Hispanic patients and in those without private insurance, and these demographic groups tended to underutilize high-volume providers. CONCLUSIONS A high-volume status for hospitals and surgeons correlates with superior value of care, as well as reduced in-hospital mortality and complications. These findings suggest that regionalization of care may enhance patient outcomes and improve value of care for patients with primary supratentorial brain tumors.