Objectives: to characterize the interventions of specialist nurses of community health and public health of a Group of Health Centers, to identify the main facilitating factors for the performance of competences, and the contribution to public health policies. Method: this is a case study carried out with nurses specialized in community health and public health nursing. Data were collected through interviews from October to December 2019. Analysis was guided by two strategies: starting from the theoretical propositions and working the data from the ground up; and two techniques: pattern matching and explanation building. Results: from the constructed matrix, ten theoretical propositions, ten emerging evidences, five patterns and five explanatory hypotheses emerged. There are interventions for epidemiological surveillance, planning and project management. Personal training and communication stand out as facilitating factors. Conclusion and implications for practice: the intervention of the nurses of these specialties presents a dimension centered on project planning and management identifies and reflects the facilitating factors of the performance of their competencies, as an applicator of public health policies