This observational study will investigate the efficacy, safety, tolerability and symptom control of GIOTRIF (Afatinib) in daily routine first-line therapy in patients with locally advanced or metastatic NSCLC harboring EGFR-mutations. Eligible NSCLC patients, for whom the treating physician has decided to initiate treatment with GIOTRIF in first line according to the local label, will be followed up for approximately 24 months.