The debate concerning if Sweden should move closer to NATO or even apply for membership is not entirely new. Due to Russia´s annexation of the Crimean peninsula in Ukraine in the spring of 2014, and due to Russians violations of national territory, Swedish political actors have discussed the NATO membership energetically. The purpose of this essay is to map out the Swedish debate about NATO membership. By applying a Pro-Contra analysis this essay will also examine arguments from the swedish parties, members of parliament, debaters, researchers and former Secretary of State. Furthermore, the arguments will also be analyzed through theories of realism and liberalism. The debate for a NATO membership shows that arguments are based on a combination of both realism and liberalism, although there are more arguments influenced by liberalism. The arguments against a NATO membership are mainly characterized by realism rather than liberalism.