Why are lung function tests important? Lung function predicts not only disability but also mortality. Vehmas and coworkers studied a total of 590 workers, originally screened for occupational lung disease, including spirometry and pulmonary diffusing capacity measurements, and were followed-up for mortality data (International Classification of Diseases-10 classification). The mean follow-up time was 10.5 years. Associations of different lung function parameters with mortality from all causes and from cardiovascular and nonmalignant respiratory diseases were analyzed. Factor analysis was used to create obstructive and restrictive factors. A total of 191 deaths were found altogether. Most measured lung function variables were associated with increased mortality when studied separately. Both decreased forced expiratory flow in one second (hazard ratio/measurement unit: 0.977; 95% confidence interval [CI]: 0.969–0.988; p < 0.001) and impaired diffusing capacity (hazard ratio/measurement unit: 0.973; 95% CI: 0.965–0.981; p < 0.001) were independently associated with mortality from all causes, as well as from cardiovascular and nonmalignant respiratory diseases. Both, obstructive factor alone, and the sum of obstructive and restrictive factors, were associated with all studied mortality categories. The restrictive factor alone was associated with all-cause and respiratory mortality. Deteriorated lung function predicts deaths. (Vehmas T, Pallasaho P, Piirilä P. Lung function predicts mortality: 10-year follow-up after lung cancer screening among asbestos-exposed workers. Int Arch Occup Environ Health 2013;86(6):667–72; Moshammer H, Neuberger M. Lung function predicts survival in a cohort of asbestos cement workers. Int Arch Occup Environ Health 2009;82:199–207.)