The purpose of this research is to identify the factors in the diffusion of an innovation - hemodialyzer re-use - and the controversy surrounding the leveling off of its use, by looking at the motivations and strategies of key actors. More particularly, this study focuses on the role of "evidence-based medicine" in the diffusion of this innovation. Starting with the observation that hemodialyzer re-use is recognized for its cost-saving while being perceived by some to be a health risk for both users and staff, our findings show that diffusion of this practice in Quebec, far from being based on solid empirical data, was instead influenced by the social phenomenon of imitation that resulted from direct contact with local dialysis centres that were at the time under great pressure from their management to reduce expenditures. The cost-savings of hemodialyzer re-use for the people managing the dialysis centres was, however, greatly reduced by several factors: the considerable investments needed to introduce this practice; the prospetcs of having to negotiate with a monopoly to purchase the hemodialyzer-dedicated equipment; and the commercial strategies of suppliers who have little interest in promoting the sale of equipment for hemodialyzer re-use over the more lucrative sale of large quintities of hemodialyzers (when not re-used). The ineffectiveness of empirical data in allaying fears of the risks associated with the practice of hemodialyzer re-use has had the dual effet of 1) causing this activity to level off, and 2) causing dialysis centres already involved in hemodialyzer re-use to adopt an approach to patient management that is based on non-tranaprency and constraint. On the conceptual level, our findings show that the likelihood of an organization adopting an innovation increases when social factors and interest factors (such as the institutional dynamic) are taken into account and align with criteria of technical rationality. Given these conclusions, we put forward some proposals for improving the potential of hemodialyzer re-use by facilitating the dialysis centres` consideration of empirical data. As well, our proposals are aimed at obtaining a stronger position for the centres with regard to their suppliers and at ensuring that both patients and clinic staff benefit more from the practice of hemodialyzer re-use