Niamh Emersom only gained international experience at the U18 World Championships 2015 in Cali , where she finished 13th with 5384 points. She then won the gold medal in the high jump at the Commonwealth Youth Games in Apia with 1.80 m and the bronze medal in the 400-meter hurdles in 61.99 s. The following year she won the bronze medal in the heptathlon at the U18 European Championships in Tbilisi with 5919 points, and in 2017 she came fourth at the U20 European Championships in Grosseto with 6013 points. In 2018 she took part in the Commonwealth Games in the Australian Gold Coast for the first time , where she won the bronze medal with 6043 points behind her compatriot Katarina Johnson-Thompson and Nina Schultz from Canada. In July, she won the U20 World Championships in Tampere with 6253 points , narrowly beating Austrian Sarah Lagger . In 2019, Emerson surprisingly won the silver medal behind Johnson-Thompson at the European Indoor Championships in Glasgow with 4731 points.