Aims:The gradient in health inequalities reflects a relationship between health and social circumstance, demonstrating that health worsens as you move down the socio-economic scale. For more than a decade, the Norwegian National government has developed policies to reduce social inequalities in health by levelling the social gradient. The adoption of the Public Health Act in 2012 was a further movement towards a comprehensive policy. The main aim of the act is to reduce social health inequalities by adopting a Health in All Policies approach. The municipalities are regarded key in the implementation of the act. The SODEMIFA project aimed to study the development of the new public health policy, with a particular emphasis on its implementation in municipalities. Methods: In the SODEMIFA project, a mixed-methods approach was applied, and the data consisted of surveys as well as qualitative interviews. The informants were policymakers at the national and local level. Results: Our findings indicate that the municipalities had a rather vague understanding of the concept of health inequalities, and even more so, the concept of the social gradient in health. The most common understanding was that policy to reduce social inequalities concerned disadvantaged groups. Accordingly, policies and measures would be directed at these groups, rather than addressing the social gradient. Conclusions: A movement towards an increased understanding and adoption of the new, comprehensive public health policy was observed. However, to continue this process, both local and national levels must stay committed to the principles of the act.