Background: LC is common and lethal; care-delivery is complex, varies in quality and outcomes, stimulating calls for multidisciplinary treatment planning (MTP) involving key specialists. This much-advocated model lacks rigorous evaluation. We conducted a prospective cohort study of MTP v Serial Care (SC) in a community healthcare system. Methods: Newly-diagnosed LC patients with performance status (PS) 0-2, and their caregivers, were enrolled from a LC multispecialty group clinic (MGC) or single-specialty general oncology clinics. A subset of general oncology clinic patients were discussed in a Multidisciplinary Thoracic Oncology Conference (MTOC), others were not (Serial Care [SC]). In this analysis, we compare MGC and MTOC patients (MTP recipients) to SC patients. Primary endpoint was overall survival (OS); secondary endpoints were measures of quality: staging practices, guideline-concordant treatment, timeliness of care, patient and caregiver satisfaction. We adjusted proportional hazards and logistic models for age, sex, histology, stage, PS, insurance, and race. Results: 254 patients received MTP v 272 SC. After a median 30 months’ follow up, there was no difference in OS (adjusted hazard ratio 1.10 [CI 0.87-1.40], p = .43). Stage-confirmatory biopsy was done in 61% MTP v 45% SC patients (adjusted odds ratio [aOR] 2.59, CI 1.74-3.86, p < .0001); 81% MTP v 68% SC patients received guideline-concordant treatment (aOR 2.04, CI 1.31-3.19, p < .002). Although the time from lesion detection to diagnostic biopsy (25 v 15 days, p = .004) or staging biopsy (29 v 20 days, p = .007) was higher with MTP, there was no difference in time to definitive treatment (60 v 57 days, p = .06). MTP patients and their caregivers reported greater satisfaction with the combined quality of care received from all team members (p < .0001) at baseline, 3 and 6 months. Conclusions: MTP for LC significantly improved the quality of care including the thoroughness of staging, use of guideline-concordant care, and patient satisfaction. Contrary to reports from retrospective analyses, timeliness of care was worse with MTP. Patient and caregiver satisfaction was superior with MTP. Despite improved quality, MTP was not associated with improved LC survival. Clinical trial information: NCT02123797