The published results of primary radiation therapy for early stage NSCLC, indicate that it is a reasonable alternative in patients with medical contraindications or who refuse surgery, resulting in acceptable morbidity, local control, and survival rates. There is no conclusive evidence that EMI is of benefit. Consequently treatment with involved field alone, may be considered when there is no evidence of hilar involvement, or when it is necessary to limit the volume of lung tissue irradiated. Although the data are not conclusive, there is evidence to suggest that the total dose of radiation delivered to the primary should be sufficient to eradicate gross disease (60 Gy or higher). Such does result in high response rates particularly for T1 tumors. There is also an indication that complete responders have better survival than other patients, suggesting that radiotherapeutic strategies to enhance tumor eradication may improve survival.