Crop landraces are genetically variable populations of agricultural plant species that through natural evolution and farmers’ selection and continuous cultivation have been adapted to the environment of their origin or cultivation. To be used and officially traded, there are more lax or strict registration schemes throughout the world concerning the application of distinctiveness, uniformity, stability (DUS) system. This review discusses the legislative framework of various countries worldwide and evaluates its application efficiency with a detailed focus on European Union (EU) experience. Especially in EU, landraces must be registered as conservation varieties in the European Catalogue of Varieties. A total of 313 agricultural and 173 vegetable conservation varieties were registered in the European Catalogues from 2013 to 2021. However, it is not clear how many of these registries are landraces because obsolete varieties are also included under the term conservation varieties. Moreover, our review reports the importance of landraces for the FAO (Food and Agriculture Organization of the United Nations) and EU strategies, namely ‘Farm to Fork’ and ‘Biodiversity’. Additionally, the DUS criteria were evaluated for their use when a crop landrace is registered taking into consideration the genetic structure of a landrace. Furthermore, the connection of landraces with Farmers’ Rights, their appropriateness for organic agriculture, and trade issues are discussed. Finally, the new proposal of European Commission on Plant Reproductive Material concerning landraces is critically reviewed and improvements are suggested.