The ADOPT-Lung study will examine disease free status (DFS) following 12 months of adjuvant durvalumab in addition to neoadjuvant chemotherapy and durvalumab in NSCLC patients who do not achieve a complete pathological response following surgery. ‘Operable’ patients will be given 3-4 cycles of neoadjuvant durvalumab and chemotherapy every 3 weeks, and provided the tumour is satisfactorily removed by surgery (R0 or R1), the patients will be randomised to 12 months of durvalumab given every 4 weeks, or observation. Participants will have CT scans every 12 weeks in the first year, and every 6 months in years 2 and 3. Blood will be collected at the scan visit to measure correlation of DFS with ctDNA clearance.