ABSO-BVOS stands for "Association Belge des Sports d'Orientation" - "Belgische Vereniging voor OriëntatieSporten" and "Belgischer Verband für OrientierungsSporte". So the name combines all the Belgian languages: French, Dutch and German.
The ABSO-BVOS has two members: VVO (Flemish league) and FRSO (French-speaking league). VVO was founded in 1987 and has around 1500 members divided over five orienteeringclubs. FRSO has around 1300 members divided over 13 orienteeringclubs.