The National Lung Screening Study has demonstrated that screening with low-dose spiral computed tomography results in fewer deaths from lung cancer compared with screening with chest radiography (CXR). Previous trials of screening with CXR and sputum cytology failed to exhibit fewer deaths compared with no screening intervention. Early computed tomography (CT) studies showed promise for CT to be a more sensitive test, yet were unable to demonstrate sufficient evidence of efficacy. This review examines the problem of early lung cancer detection, the issues presented by screening, and results of past and recent studies of lung cancer screening.