Introduction:
Little is known about the implementation of smoking bans at the level of European municipalities. The study analyzes the importance and development of smoke-free (SF) environments in 7 EU cities (in GER, IRL, FIN, POR, NED, ITA, BEL) with the aim of categorizing existing implementation processes, and recommending enhancement for future SF policies in Europe.

Methods:
A semi-structured interview guide has been developed, in order to perform 56 expert interviews with local stakeholders & decision makers in 7 EU cities. All interviews were conducted and transcribed in the respective native languages, and afterwards translated into English. Data has been analyzed inductively by applying an empirically grounded type construction that has been linked with deductive realist elements of context-mechanism-outcome-configurations (CMOs).

Results:
The findings show that SF environments are mostly adopted at national levels, but differently implemented at local levels due to varying context factors, such as the level of collaboration, enforcement strategies, and existing SF legislation. Four implementation types (“progressive-hungry” vs. “moderate-rational” vs. “upper-saturated” vs. “lower saturated”) can be distinguished, which differ mainly in regard to their engagement in enhancing existing and future SF environments as well as along their level of tobacco de-normalization and perceived smoking visibility. Major mechanisms to enhance/expedite future SF regulations (indoor & outdoor) were found to be intersubjective comprehensible arguments, such as scientific evidence, public support, and the child frame. However, counter-mechanisms like smokers’ or tobacco industry resistance as well as minor prioritization and de-normalization can hinder perceived importance and sustained development of SF environments.

Discussion:
Different priorities and legislative conditions lead to largely varying CMOs and implementation strategies in Europe. Still, future SF policies can be enhanced by reasonable arguments and the growing importance of tobacco de-normalization.

Funding:
This study (SILNE-R) is supported by EU Horizon 2020 (grant agreement 635056).