Rank in Judo are ranked in ascending numerical order. The ninth ("kudan") and tenth degree black belt ("jūdan") and, theoretically, those higher, have no formal requirements. Only 15 individuals have been promoted to the rank of Kōdōkan 10th dan. On January 6, 2006, three individuals were promoted to this rank simultaneously: Daigo Toshirō, Ichirō Abe, and Ōsawa Yoshimi. This is the most ever at the same time, and the first in 22 years. No one has ever been promoted to a rank higher than 10th "dan", but in theory the Judo rank system is not limited to 10 degrees of black belt. The
Judo in Canada (brown belt). Later, when he travelled to Japan as Prime Minister, he was promoted to "sho-dan" (first-degree black belt) by the Kodokan, and then promoted to "ni-dan" (second-degree black belt) by Masao Takahashi in Ottawa before leaving office. Trudeau began the night of his famous 'walk in the snow' before announcing his retirement in 1984 by going to Judo with his sons. Other Canadian politicians and their families have also been associated with Judo. The children of Trudeau's successor in office, Brian Mulroney, also practised at the Takahashi Dojo, and Judo Canada has presented two honorary black belts to Members