Yanai entered the Ministry of Foreign Affairs in 1961, and studied at the University of Strasbourg while in France.

[4] He was removed from his post due to a scandal involving bureaucrats in the Foreign Ministry.

[4] On 1 October 2011, he was elected to succeed José Luís Jesus as President of the ITLS for a three-year term.

[6] He headed an advisory panel on Japanese self-defence during both of Shinzō Abe's terms as prime minister.

[7] The panel consisted of thirteen security experts,[8] and was concerned with amendments to Article 9 of the Japanese Constitution.