This article examines the restriction of smoking on university campuses in the Canadian context. Indoor smoking on campus is now completely prohibited by law, and universities are increasingly moving to restrict, or prohibit, outdoor smoking on their grounds. The research focuses on three case studies to identify changes in spatial restrictions on campus smoking over the last four decades (1970–2010), and to determine the challenges involved in establishing bans in outdoor areas of campus. The three universities were selected for their different approaches to the issue of outdoor smoking. Data collection involved semi-structured interviews with 36 key informants, conducted from September 2010 to January 2011, supplemented by documentary information. Interview data were analysed thematically. Protection against environmental tobacco smoke (ETS) on campus proceeded incrementally, via policy-making at the provincial, municipal and institutional levels. Historically, institutional bans on indoor smoking were particularly significant, but their health benefits could be limited by the presence of private property on campus. Universities continue to initiate smoking restrictions today, with respect to outdoor bans. However, respondents reported myriad challenges in developing, implementing and maintaining such bans. Five principal concerns were articulated: the need for ongoing policy communication; management of community relations as smokers are displaced from campus; enforcement to ensure that the policy has practical effect; safety concerns; and difficulties relating to campus layout. Because challenges are diverse and contextual, effective protection against outdoor ETS on campus is likely to require an ongoing commitment on the part of administrators.