Although some shared characteristics may be found among folk high schools in the Nordic countries - such as the role as a pedagogical alternative to the public-school system, the frequency of boarding schools and the informal relations between teacher and student - they have originated and developed differently. Based on previous research, this introduction points out such national differences related to both philosophical foundations and geopolitical factors. Before introducing the articles for the thematic issue, a table is presented which depicts the number of folk high schools, offered credits and types of courses in each country.