Inclusion Criteria:

1. Male and female patients aged 18 to 75 years inclusive, with histologically confirmed metastatic NSCLC will be enrolled.
2. Patients must have not previously been treated with anticancer drugs.
3. ECOG performance status of 0 - 1.
4. Life expectancy of at least 12 weeks.
5. Patients must be able to take oral medication.
6. At least 4 weeks since any prior surgery or radiotherapy. Patients who, in the opinion of the investigator, have fully recovered from surgery in less than 4 weeks may also be considered for the study
7. Granulocyte count > 1,500/mm3 and platelet count > 100,000/mm3. Haemoglobin ³ 9.0g/dl.
8. SGOT (AST) and SGPT (ALT) < 2,5 x ULN in the absence of liver metastases or up to 5 x ULN in case of liver metastases
9. Alkaline phosphatase (ALP) < 2,5 x ULN. If alkaline phosphatase is > 2.5 x ULN, SGOT (AST) and SGPT (ALT) must be < 1.5 x ULN. If alkaline phosphatase is ³ 2.5 x ULN in the presence of liver metastases, SGOT and SGPT must be < 5 x ULN
10. Serum creatinine £ 1.5 ULN or creatinine clearance > 60 ml/min.
11. Normal serum calcium.
12. For all females of childbearing potential a negative pregnancy test must be obtained within 48 hours before starting Tarceva/placebo treatment.
13. Patients with reproductive potential must use effective contraception.
14. Able to comply with study and follow-up procedures.
15. Written (signed) Informed Consent to participate in the study.
16. Written (signed) Informed Consent for use of tumour samples.
17. Patients must be able to effectively read, and understand the local language(s) for which Quality of Life rating scales are available.
18. Formalin-fixed, paraffin-embedded tumour tissue samples representative of the tumour will be provided to sponsor within 3 weeks of the patient starting chemotherapy

Exclusion Criteria:

1. Prior exposure to agents directed at the HER axis (e.g. gefitinib, cetuximab, trastuzumab).
2. Prior chemotherapy or therapy with systemic anti-neoplastic therapy (e.g., monoclonal antibody therapy) for advanced disease. Prior surgery and/or localised irradiation is permitted.
3. Patients who have undergone complete tumour resection after responding to platinum based chemotherapy.
4. Any unstable systemic disease (including active infections, significant cardiovascular disease, [including myocardial infarction within the previous year], any significant hepatic, renal or metabolic disease) metabolic dysfunction, physical examination finding, or clinical laboratory finding that contraindicates the use of study medication(s) or that might affect the interpretation of the results or render the patient at high risk from treatment complications.
5. Any other malignancies within 5 years (except for adequately treated carcinoma in situ of the cervix or basal or squamous cell skin cancer).
6. Patients are excluded if they have brain metastasis or spinal cord compression that has not yet been definitively treated with surgery and/or radiation; previously diagnosed and treated CNS metastases or spinal cord compression without evidence of stable disease (clinically stable imaging) for at least 2 months will also cause patients to be excluded.
7. Patients who are at risk (in the investigator's opinion) of transmitting human immunodeficiency virus (HIV) through blood or other body fluids are excluded.
8. Any inflammatory changes of the surface of the eye.
9. Patients who cannot take oral medication, who require intravenous alimentation, have had prior surgical procedures affecting absorption, or have active peptic ulcer disease.
10. Nursing and/or pregnant women.
11. Hypersensitivity to erlotinib (Tarceva) or to docetaxel or to any of the excipients.