PURPOSE OF REVIEW: The current status of postoperative adjuvant therapy for nonsmall cell lung cancer (NSCLC) is reviewed. RECENT FINDINGS: Cisplatin-based postoperative chemotherapy is a current standard of care for patients with stage II-III NSCLC who underwent complete resection. However, its benefit is limited. In these 20 years, the introduction of targeted therapies and immune checkpoint inhibitors has dramatically changed the treatment of metastatic lung cancer. The accumulated knowledge is now being applied in the adjuvant setting and many clinical trials are underway. Recently, postoperative osimertinib was shown to greatly prolong disease-free survival of patients with resected, stage II/IIIA NSCLC with EGFR mutation with an unprecedented hazard ratio of 0.17 in ADAURA study. Furthermore, initial results of adjuvant studies of immune checkpoint inhibitors are expected to be reported shortly. SUMMARY: As lung cancer is inherently prone to metastasize even though it looks in its earlier stage, it is essential to develop a newer generation of adjuvant therapies to improve patient outcomes. To this end, international and multidisciplinary collaboration is key to establish a new standard of care. It is anticipated that the treatment algorithm of early-stage lung cancer will be completely revised in 5 years using a more individualized approach.