Lung cancer is the leading cause of cancer-related deaths. Non-small cell lung cancer (NSCLC) accounts for approximately 86% of patients with lung cancer. The two most powerful predictors of long-term outcome in patients with NSCLC are the stage and performance status (PS) at diagnosis. Although the cure rates of patients with resected stage I and II NSCLC are 50% and 40%, respectively, only 20% of patients treated with chemotherapy and radiation for locally advanced NSCLC are cured of their illness. Patients with metastatic NSCLC do not have curative potential with available therapies. Outcome for patients with NSCLC and poor PS is dismal. Patients with localized disease and poor PS are treated with radiation therapy. Patients with locally advanced NSCLC are treated with sequential chemotherapy, followed by radiation therapy. The suggested treatment options for patients with metastatic disease and poor PS are single-agent chemotherapy or supportive care.