This article examines exposure to second-hand smoke (SHS) in 2003 in various settings by age and sex, and compares exposure indicators by province and health region.The data are from the 2000/01 and 2003 Canadian Community Health Survey, conducted by Statistics Canada.Rates of exposure to SHS among non-smokers are calculated by sex, age and location for the household population aged 12 or older. Rates of exposure at work are examined for employed non-smokers aged 15 or older. Smoking prevalence is expressed as a percentage of the household population aged 12 or older.In 2003, 33% of non-smokers reported that they were regularly exposed to SHS. The risk of exposure was greatest in public spaces, but regardless of setting, rates of exposure were higher for men than women. Exposure rates varied by age and peaked in young adulthood. However, at home and at work, the younger the non-smokers, the more likely they were to be exposed to SHS. Disparities in SHS exposure by province/territory and by health region were substantial.