Passive smoking is the third leading but preventable cause of death worldwide. It is associated with an elevated risk of developing acute respiratory diseases, obstructive lung disorders, lung cancer, and cardiovascular disease. Whereas the dose-response relationship between second-hand smoke exposure and respiratory diseases is likely to be linear, a non-linear dose-response curve has been observed with respect to acute cardiovascular events. This explains the disproportionately high risk of myocardial infarction among passive smokers as compared to unexposed individuals. Over the last ten years, exposure to second-hand smoke has declined in Germany, but it is still substantial. With passive smoking in the home being a difficult target for preventive measures, public smoking bans have recently been shown to greatly reduce second-hand smoke-related morbidity and mortality. In addition, such measures are usually well tolerated and highly relevant regarding legal aspects related to workplace issues. This article summarises the current evidence on the health consequences of passive smoking and on the favourable effects of public smoking bans.