Lung cancer is currently one of the most common malignant diseases and is responsible for substantial mortality worldwide. Compared with never smokers, former smokers remain at relatively high risk for lung cancer, accounting for approximately half of all newly diagnosed cases in the US. Screening offers former smokers the best opportunity to reduce their risk of advanced stage lung cancer and there is now evidence that annual screening using low-dose computed tomography (LDCT) is effective in preventing mortality. Studies are being conducted to evaluate whether the benefits of LDCT screening outweigh its costs and potential harms and to determine the most appropriate workup for patients with screen-detected lung nodules. Program efficiency would be optimized by targeting high-risk current smokers, but low uptake among this group is a concern. Former smokers may be invited for screening; however, if fewer long-term current smokers and more former smokers with long quit duration elect to attend, this could have very adverse effects on cost and screening test parameters. To illustrate this point, we present three possible screening scenarios with lung cancer prevalence ranging from between 0.62 and 5.0 %. In summary, cost-effectiveness of lung cancer screening may be improved if linked to successful smoking cessation programs and if better approaches are developed to reach very high-risk patients, e.g., long-term current smokers or others based on more accurate risk prediction models.