The last several years have seen a wealth of new evidence on the health effects of exposure to second-hand tobacco smoke (SHS), the benefits of smoke-free environments and best practice in implementing smoke-free policies. Compiling and disseminating this evidence is critical to raising awareness among decision-makers and public health advocates about the necessity for smoke-free environments to protect health and their broad acceptance and endorsement. It is for this reason that WHO is now publishing policy recommendations on protection from SHS exposure.