The Mediterranean Basin is a hotspot for biological and cultural diversity, and this is particularly evident in its islands, even though little attention has been paid to their remarkable biocultural diversity. In order to elucidate this characteristic phenomenon, we present a review of the literature on biodiversity and cultural studies in Sardinia. From the review, it has emerged that the island can serve as an excellent case study and a model for the development of a methodology on the topic, which can be applied to the entire Mediterranean Basin. An Island Biocultural Diversity Initiative for the Mediterranean Region has therefore been set up to support the preservation of biocultural diversity and Traditional Ecological Knowledge (TEK) in Mediterranean islands, with Sardinia as its primary hotspot.