For the use of immunotherapy in metastatic non-small cell lung cancer (NSCLC), the NCCN Guidelines for NSCLC reflect the importance of assessing levels of PD-L1 expression to determine the best use of PD-1/PD-L1 inhibitors, whether alone or in combination with chemotherapy. Patients who lack a driver mutation and have tumor PD-L1 expression ≥50% are recommended to receive single-agent pembrolizumab, although combining with carboplatin/pemetrexed is also a reasonable choice, especially if there is higher burden of disease. For tumors with PD-L1 expression <50%, it is important to distinguish between nonsquamous and squamous cell carcinoma (SCC). For patients with non-SCC disease, pembrolizumab + carboplatin/pemetrexed is preferred. Alternately, a 4-drug regimen of carboplatin/paclitaxel/bevacizumab/atezolizumab is reasonable, especially for patients ineligible for pemetrexed. In patients with SCC, carboplatin + paclitaxel or nab-paclitaxel with pembrolizumab is a category 1 recommendation. Tumor mutational burden is emerging as a biomarker for efficacy but is not yet ready to be used in patient selection. Optimal management of the unique toxicities associated with immunotherapy, which can be more frequent with these combinations, is also critical for good outcomes.