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Challenges for the formulation, implantation and implementation of a National Health Surveillance Policy in Brazil.

This article examines the evolution of health surveillance policies as actions, models and systems, as well as contributing to the debate about the constitution of the National Health Surveillance Policy (PNVS). The article discusses conceptual elements regarding the notion of health surveillance and its evolution in Brazil and a trajectory is provided in relation to the construction of care models, particularly after the creation of the Unified Health System (SUS). The possibility of using the framework of public policies based on evidence, and methods for analyzing health situations, such as spatial analysis and time series, are highlighted. To conclude, questions are raised regarding the effective creation of the PNVS, and the challenges that the federal executive faces in driving this process.