This paper provides a cost-benefit analysis of a participatory ergonomics program conducted at the beginning of the 1990s to reduce back-related disorders among packers at a warehouse of the Société des Alcools du Québec in Quebec City. After evaluating the costs of the program, we present a rigorous econometric analysis to assess how many accidents have been prevented by the program so as to compute the direct and indirects costs avoided as a result of such accident reduction. We show that the program has indeed been profitable for the firm.