Background:
In 2008 115.000 children in Flanders were daily exposed to the smoke of their parents' cigarettes. We tried to decrease that number by means of the campaign ‘Smoking inside is never okay' that consisted of
1) a mass media campaign that intended to raise smoking parents' awareness of the harmful effects of secondhand and thirdhand smoke and to encourage them to smoke outside;
2) tools to help intermediaries discuss the subject with smoking parents.

Objective:
Evaluate the effects as well as the strengths and limitations of the campaign.

Methods:
An inquiry of parents by phone to map behavioral changes and to find out which parents still smoke in the presence of children.

Results:
Since 2008 the number of children that are daily exposed to the smoke of their parents' cigarettes decreased from 115.000 to 29.000. This decrease is mainly due to the steadily declining number of smoking parents, but there has also been a behavioral change. The awareness of the dangers of SHS has grown and a large majority of parents have adapted their smoking habits. The number of smoking parents stays the highest in the low-income group. Furthermore, more than half of them still smoke when their children are around, and if they do so, they do it more often at home and in the homes of their family/friends.

Conclusion:
‘Smoking inside is never okay' has proven to be a successful campaign to change the behaviour of smoking parents. However mass media campaigns have their limitations. Smoking parents in lower income groups seem less perceptive to the message of the campaign. Furthermore, most of them think smokers should be left alone. To achieve a change in these parents' smoking behaviour a more personalized intervention is needed.