Background: Subgroup analyses of JBR.10 and the LACE meta-analysis suggest that the elderly benefit from ACT with acceptable toxicity. Here we evaluate uptake of ACT and its impact on outcome by age group in the general population of Ontario. Methods: All NSCLC cases surgically resected in Ontario 2001-2006 were identified from the population-based Ontario Cancer Registry. Electronic treatment records were linked to the registry. Uptake of ACT was compared across age groups: <70, 70-74, 75-79, 80+ years. As a proxy of benefit from ACT, we compared survival of cases diagnosed in 2004-2006 to 2001-2003 (ACT trials reported in 2004). Hospitalization rates within 6 months of surgery served as a proxy of treatment related toxicity. Results: 2763/6304 (44%) eligible cases were elderly (≥70 yrs). The elderly were more often male, had more co-morbidities and longer postoperative stays. They were less likely to have adenocarcinoma, undergo pneumonectomy or be treated at a regional cancer center. Uptake of ACT in the elderly increased from 3.3% in 2001-2003 to 16.2% in 2004-2006 (p<0.001). Adoption of ACT declined with age: 43% in <70yrs, 23% in 70-74yrs, 13% in 75-79yrs and 5% in 80+yrs (p<0.001). Among evaluable elderly cases 70% received cisplatin, 28% carboplatin (versus 85% and 14% of cases <70yrs [p=0.005]). Dose modifications and drug substitutions were similar across age groups. In the elderly, 4-yr survival increased from 47.1% in 2001-2003 to 49.9% in 2004-2006 (p=0.01). Hospitalization rates within 6-24 weeks of surgery were similar across the age groups (p=0.54). Age, pathological stage, and geographical region were independently associated with receipt of ACT in the elderly. Conclusions: Adoption of ACT in the elderly was associated with significant improvement in overall survival without apparent increase in severe toxicity as judged by hospital admission. Our findings confirm that the benefits of ACT in the elderly, suggested by the relevant clinical trials, are being realized in the general population. Efforts to understand and improve underutilization of ACT in the elderly in clinical practice are needed.