In the United States, lung cancer is the second most common diagnosed cancer and the leading cause of cancer-related death. Though tobacco smoking is the major risk factor accounting for 80 to 90% of all lung cancer diagnoses, there are numerous other risk factors that have been identified as casually associated with lung cancer etiology. However, there are few causally-linked risk factors for lung cancer diagnosed among never smokers which, if considered a unique reportable category, is the 11th most common cancer and the 7th leading cause of cancer-related death. Lung cancer survival has only marginally improved over the last several decades, but the availability of screening and early detection by low-dose computer tomography and advances in targeted treatments and immunotherapy will likely decrease mortality rates and improve patient survival outcomes in the near future.