The Thomas Cup is an international teams competition for the supremacy in men's badminton. For the Thomas Cup 1961, 18 national teams were divided in 4 groups; namely, Asia, Australasia, Europe, and America. The four zone winners would then play a second round (the Inter-zones play-offs) in Jakarta, Indonesia, for the right to face the defending champion, Indonesia, who was exempted from earlier rounds, in a conclusive Challenge Round. For a more detailed description of the Thomas Cup format, see Wikipedia's general article about the Thomas Cup.