Erlotinib is an orally active inhibitor of the epidermal growth factor receptor that is effective for the treatment of non-small-cell lung cancer (NSCLC). Patients with a poor performance status (PS) of 2 constitute up to 40% of advanced NSCLC. This group of patients have a lower life expectancy and are thought to have a greater degree of treatment-related toxicity. The clinical benefit on 238 patients with poor PS included in an open-label, nonrandomized, phase II trial of erlotinib in advanced/metastatic NSCLC was 57.58% defined as complete response plus partial response plus stable disease. Median time to progression was 2.9 months. This review will summarize available data about erlotinib on patients with a PS of 2.