Background Jacques-Cartier Bridge in Montreal, Canada, was one of the sites with the highest number of suicides in North America. Following extensive research and lobbying by an expert group, a suicide prevention barrier was constructed on the bridge.

Aims/Objectives/Purpose (1) To analyse factors contributing to the successful implementation of this suicide prevention initiative; (2) To investigate if the barrier led to displacement of suicides to other jumping sites.

Methods We used Shiffman and Smith's Political Priority Framework to analyse the characteristics, ideas, actor strength, and political context associated with the initiative. Poisson regression was used to assess changes in annual rates of suicide by jumping from Jacques-Cartier Bridge, other bridges and other sites after installation of the suicide barrier.

Results/Outcomes The presence of powerful, credible and committed actors and coherence of ideas used to convey messages about suicide and its prevention, based on scientific evidence, were important for the success of the prevention initiative. Support of the media was also critical. Results show no evidence of displacement to other jumping sites after installation of the barrier.

Significance/Contribution to Field The study provides useful information on the successful implementation of a public health initiative at a local level that can inform future policy initiatives, not only for suicide prevention but other health outcomes. The barrier on Jacques-Cartier Bridge was effective in reducing suicides. The design of a barrier is important for its effectiveness and is preferably considered in the construction of new bridges with the potential to become symbolic suicide sites.