An ontology in the area of Crop Wild Relatives (CWR) has recently been developed in a joint effort between Bioversity International and the Food and Agriculture Organization. The ontology is now accessible online in 4 languages (English, French, Spanish and Russian). The hierarchy can be browsed in a tree-like view and the labels and relationships can be accessed via each concept's detail view. Further work to integrate the ontology with the CWR portal is ongoing.