This study will evaluate Tarceva in a selected population of patients with untreated advanced non-small cell lung cancer who are anticipated to have a relatively good (indolent) prognosis based on clinical criteria. It is anticipated that selection will enrich for tumor characteristic that are likely to be benefited by EGFR inhibitor treatment (survival greater than 90 days). The goal of this strategy is to provide a less toxic, oral treatment for patients with advanced NSCLC that will not interfere with patients receiving chemotherapy at some point in the future and may prolong the time to chemotherapy related progression.

Patients will remain on study until disease progresses, a decline in performance status, if patient cannot tolerate the side effects or develops symptoms requiring conventional chemotherapy.

Primary Objective To determine Time to Chemotherapy Progression (ie includes time on Tarceva monotherapy and chemotherapy) in advanced NSCLC

Secondary Objectives To evaluate survival and response rate associated with Tarceva treatment To study the frequency of symptom improvement (Lung Cancer Subscale)

Inclusion Criteria:

• Performance status 0-1.
• Weight Loss < 10% in preceding 3 months
• Age 18 years and older.
• Adjuvant chemotherapy allowed if > 6 months from protocol entry
• Adequate Organ Function
• Liver enzymes < 2X normal, bilirubin = normal
• Oxygen saturation> 89% on room air unless chronically oxygen dependent (not cancer related)
• Creatinine <2.0 mg

Exclusion Criteria:

• Not pregnant or lactating.
• No Clinical Brain Metastases
• No prior chemotherapy for systemic disease
• Imminent need for chemotherapy for impending organ dysfunction is not allowed