Smoking bans offer practical protection against environmental tobacco smoke and highlight the decreasing normative status of smoking. At Canadian universities, indoor smoking is now completely prohibited, but regulations vary with respect to outdoor smoking. The purpose of this research was to conceptualize the interactions of smoking bans on campus with changing social norms around smoking. Interviews were conducted with 36 key informants, exploring the development and normative significance of smoking bans at three case study institutions. Five key themes were identified in the transcripts. First, universities were understood as community leaders and role models. Second, they were viewed as institutions with a mandate to promote health. Third, students were generally perceived to view smoke-free environments and lifestyles as normative. Fourth, respondents also acknowledged that students remain vulnerable to social and behavioural influences that can encourage smoking. Finally, they articulated bans' normative effects: restricting where smoking occurs on campus may discourage initiation and support cessation. Our findings suggest that health-promoting policies, such as smoking bans, can be motivated by changes in social norms and that their implementation reinforces this norm shift. Moreover, the contextual and compositional characteristics of universities mean they are uniquely placed to adopt such initiatives.