Several milestones in the systemic treatment of lung cancer have been reached. Combination chemotherapy of small cell lung cancer was the first of these milestones. The establishment of palliative chemotherapy in patients with advanced non-small cell lung cancer and of adjuvant chemotherapy in patients with completely resected non-small cell lung cancer was another important milestone. Targeted therapies with angiogenesis inhibitors, EGFR inhibitors, and ALK inhibitors also advanced treatment. The clinical introduction of immune checkpoint inhibitors was the latest milestone.