This article deals with the question of whether regional cultural competence centers foster the diversity of cultural expressions and how the objectives of the United Nations Educational, Scientific, and Cultural Organization's (UNESCO) Convention on Cultural Diversity are implemented. By introducing the Convention on Cultural Diversity, the conditions of regional cultural policy governance, and the idea of regional cultural competence centers, a framework for evaluation is outlined. The evaluation of four regional cultural competence centers in the Swiss Central Region shows that fostering cultural diversity is complex and has many different approaches and effects. The final discussion concludes that principles such as interculturality, freedom, and access for all under the Convention on Cultural Diversity can promote a diversity of cultural expressions but that these criteria have to be set from outside - for example, by public funding institutions - so that regional actors implement them.