Inclusion Criteria:

- Written informed consent.

- Age >= 18 years.

- Histologically or cytologically documented inoperable, locally advanced (stage IIIb
with malignant pleural or pericardial effusion) or metastatic (Stage IV) NSCLC.

- Patients who have failed only one prior chemotherapy to treat the advanced disease
and candidates to receive a second line treatment.

- ECOG PS 0-2.

- Adequate hematological function: hemoglobin => 9 g/dl; neutrophils count => 1.5 x
10(9)/l; platelet count => 100 x 10(9)/l.

- Adequate liver function: Bilirubin <= 1,5 x ULN; AST and ALT <= x 3 ULN when no
hepatic metastases or <=5 x ULN if hepatic metastases; Alkaline phosphatase <=5 x UNL
except that there is hepatic metastases.

- Adequate renal function: Calculated creatinine clearance => 40 mL/min (Cockroft y
Gault) or serum creatinine <= 1.5 x ULN .

- Patient able to meet the requirements of the study and accessible for correct
follow-up.

- Oral swallowing capability.

Exclusion Criteria:

- Previous treated with more than one chemotherapeutic treatment for NSCLC

- Concomitant treatment with another drug under investigation.

- Pregnancy or lactation. Fertile women must provide a negative result of pregnancy
test (in serum or urine) within 7 days prior to study treatment start. In addition,
they must use an effective method of contraception (oral contraceptives, intrauterine
device, barrier methods of contraception, together with spermicidal jelly or surgical
sterilization) during the study.

- Evidence of other disease, metabolic or neurological dysfunction, physical
examination finding, or clinical laboratory finding giving reasonable suspicion of a
disease or condition that contraindicates use of an investigational drug or patient
at high risk from treatment complications.

- Contraindication for the use of erlotinib or docetaxel.