Public health systems across high income and middle income countries are facing unprecedented pressure to respond to complex population health challenges that are shaped by social inequities, stigma, rapidly changing disease patterns, and growing demands for accountability. Within this context, the importance of evidence informed decision making has been repeatedly emphasized as a core principle of effective public health practice. However, despite decades of advocacy for evidence based and evidence informed public health, a persistent gap remains between what research suggests should be done and what is actually implemented in everyday policy and practice. This gap is not merely technical but is deeply rooted in organizational culture, workforce capacity, governance structures, and the broader social and political environment in which public health agencies operate. Drawing on a comprehensive body of literature from Canada and other comparable health systems, this article develops an integrated theoretical and empirical analysis of how evidence informed public health can be strengthened through deliberate investments in workforce development, organizational change, and knowledge translation infrastructure.

The article situates evidence informed public health within a broader commitment to health equity and stigma reduction, arguing that evidence is not value neutral but must be interpreted and applied through an inclusive lens that recognizes structural disadvantage and lived experience. It draws on systematic reviews of public health interventions, workforce training programs, and implementation strategies to show that evidence informed approaches are associated with improved population health outcomes and strong economic returns, but only when they are supported by enabling organizational and system level conditions. Using conceptual frameworks such as the COM B model and the behaviour change wheel, the article explains how individual knowledge, motivation, and skills interact with organizational opportunity structures to shape evidence use in practice.