Lung cancer remains the leading cause of cancer-related deaths in men and women. Lung cancer screening (LCS) computed tomography (CT) offers the opportunity to identify lung cancer early when it is treatable and potentially curable. Use of appropriate low-dose CT technique and structured reporting are important factors for high-quality screening. The diagnosis of lung cancer may occur as a result of CT screening or diagnostic imaging done for symptoms. A chest radiograph (CXR) or CT can reveal a suspicious lung nodule or mass needing further evaluation. The radiologist uses structured reporting systems such as Lung-RADS for screening and Fleischner Society guidelines for incidental lung nodules to recommend further work-up for the findings on CT. A multidisciplinary committee review can help determine the best next steps for management of patients with highly suspicious nodules. Care escalation involving PET-CT and/or tissue sampling is sometimes indicated. The ninth edition of the TNM Staging System for Lung Cancer has recently been released. CT imaging, PET-CT, and image-guided procedures have key roles in the accurate clinical staging of lung cancer.