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Lung cancer has the highest mortality rate of any cancer in Canada, causing 25.5% of all cancer deaths, with a 5-year survival rate of only 19%. More than half of lung cancers are metastatic at diagnosis, with common sites of metastases in the brain, bone, liver, and adrenal glands. Lung cancer is a heterogeneous group of cancers broadly separated into small cell lung cancer (SCLC)—approximately 15% of all lung cancer cases—and non–small cell lung cancer (NSCLC), which is further divided into predominantly adenocarcinoma and squamous cell carcinoma subtypes. More than 80% of lung cancer cases are related to smoking, meaning smoking cessation remains the cornerstone of lung cancer prevention. Low-dose computed tomography is a valuable screening tool for lung cancer that can identify lung cancers at an earlier stage and reduce lung cancer–specific mortality and all-cause mortality. Although lung cancer screening is recommended by the Canadian Task Force on Preventive Health Care, it is currently available in only a few Canadian provinces.