As well as changing the daily lives of modern societies, information and communication technology (ICT) has changed the way countries store their intellectual property, how they deliver their digital services and how they control their critical infrastructures. Nations have become dependent on ICT and disruptions caused by vulnerabilities or sabotage in these infrastructures can compromise national sovereignty. In this scenario, many countries have created security strategies to protect themselves in cyberspace. This paper presents the concepts for establishing a national cyber security strategy using the Grounded Theory research method. At the end of the analysis, a conceptual model was designed and its adherence was studied by comparing it with the cyber strategies of some countries. It shows that concepts are not definitive, but dynamic, and that the proposed model can be an alternative for creating national cyber strategies or revising existing initiatives.