The primary objective of this open-label, single arm Phase II trial is to explore the efficacy of BIBW 2992 defined by the objective response rate (CR, PR) as determined by the RECIST criteria, in patients with advanced NSCLC Stage IIIB or IV whose tumours harbour activating mutations within exon 18 to exon 21 of the EGFR receptor, in patients with mutations in the HER2/neu receptor and in patients with EGFR FISH positive tumours with no EGFR mutations.