Sii wad qodobkan - Aitken wuxuu ka bartay chess aabihiis isagoo 10 jir ah. Wuxuu ahaa horyaalkii Scotland 1935, 1952, 1953, 1955, 1956, 1957, 1958, 1960, 1961 iyo 1965, kii dambe oo ay wada shaqeyn la lahaayeen PM Jamieson. Wuxuu sidoo kale noqday Horyaalka London 1950. Sanadkii 1959 wuxuu helay natiijada ugu wanaagsan ee horyaalka Ingiriiska, isagoo ku dhammeystay kaalinta toddobaad. Aitken wuxuu Scotland u matalay afar olympiad oo shaashad ah. Wuxuu ku ciyaaray guddiga ugu sarreeya ee Stockholm 1937, isagoo dhaliyay kaliya 32.4% laakiin wuxuu ka adkaaday GM-ga Sweden ee Gideon Ståhlberg wuxuuna barbaro la galay GM-ga Mareykanka ee Samuel Reshevsky. Wuxuu ciyaaray kulankii labaad ee Munich 1958
iyo Tel Aviv 1964, oo leh dhibco 67.6% iyo 28.1% siday u kala horreeyaan. Aitken wuxuu ciyaaray shaxda lixaad ee Skopje 1972, isagoo dhaliyay 38.9%.