Based on the ‘Management of Stage III Non-Small-Cell Lung Cancer: ASCO Guideline’, this summary document makes recommendations directly related to RT for the practicing radiation oncologist about best practices on the use of RT in the neoadjuvant, adjuvant, and unresectable settings given the current clinical evidence available. Unresectable patients with stage III NSCLC should ideally be managed with combined concurrent chemoradiation using a platinum-based doublet with a standard radiation dose of 60 Gy followed by consolidation durvalumab in patients without progression after initial therapy.