Allen started for the Skating Club of New York. In 1964 and 1966 he was American champion . From 1962 to 1968 he took part in all world championships and, with the exception of his first world championship, where he was eighth, always placed in the top five. In 1965 he was runner-up behind Alain Calmat . He won the bronze medal at the 1964 Olympics , two days before his 15th birthday, making him the youngest ever medalist at the Olympics. To this day he is the youngest male medalist and the youngest individual athlete to have succeeded. It should be noted here that the US figure skating had lost the best figure skaters and figure skating coaches in the country due to the plane crash of Sabena Flight 548 in 1961.