The men's 4 × 400 metres relay at the 2009 World Championships in Athletics was held at the Olympic Stadium on August 22 and August 23.
The women's 400 metres hurdles competition at the 2016 Summer Olympics in Rio de Janeiro, Brazil was held at the Olympic Stadium between 15 and 18 August.
The women's 4 × 400 metres relay competition at the 2016 Summer Olympics in Rio de Janeiro, Brazil was held at the Estádio Olímpico João Havelange on 19–20 August.
The women's 4 × 400 metres relay at the 2015 World Championships in Athletics was held at the Beijing National Stadium on 29 and 30 August.
The men's 4 × 400 metres relay at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 12 August.
The women's 400 metres hurdles at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 7−8 and 10 August.
The women's 4 × 400 metres relay at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 12–13 August.
The women's 400 metres hurdles event at the 2020 Summer Olympics took place between 31 July and 4 August 2021 at the Japan National Stadium. 39 athletes from 25 nations competed.
The women's 4 × 400 metres relay event at the 2020 Summer Olympics took place on 5 and 7 August 2021 at the Japan National Stadium. There were 16 competing relay teams, with each team having at least 5 members from which 4 were selected in each round.
The men's 400 metres at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha on 1, 2 and 4 October 2019. The winning margin was 0.67 seconds which as of 2024 is the greatest winning margin in the men's 400 metres at these championships since the retirement of Michael Johnson.
The men's 400 metres hurdles at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha from 27 to 30 September 2019.
The women's 200 metres at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 30 September to 2 October 2019.
The women's 400 metres at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 30 September to 3 October 2019.
The women's 4 × 400 metres relay at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 5 to 6 October 2019. In the final the Jamaican team were initially disqualified, but were reinstated as the bronze medallists upon appeal.
The men's 4 × 400 metres relay at the 2019 World Athletics Championships was held at the Khalifa International Stadium in Doha, Qatar, from 5 to 6 October 2019.
The men's 400 metres hurdles at the 2022 World Athletics Championships was held at the Hayward Field in Eugene from 16 to 19 July 2022.
The women's 400 metres hurdles at the 2022 World Athletics Championships was held at the Hayward Field in Eugene, Oregon, United States, from 19 to 22 July 2022. It was won by Sydney McLaughlin in a world record time of 50.68 seconds. The winning margin was 1.59 seconds which as of 2024 stands as the greatest winning margin for the women's 400 metres hurdles at these championships.
The women's 400 metres at the 2023 World Athletics Championships was held at the National Athletics Centre in Budapest, Hungary from 20 to 23 August 2023. The winning margin was 0.81 seconds which as of 2024 is the only time the women's 400 metres has been won by more than 0.7 seconds at these championships.
The women's 400 metres hurdles at the 2023 World Athletics Championships took place in three rounds at the National Athletics Centre in Budapest, Hungary from 21 to 24 August 2023. On 21 August, forty-one athletes of thirty nations participated in the five heats of round 1. On 22 August, twenty-four athletes competed in the three heats of the semifinals. On 24 August, eight athletes competed in the final, which was won by Femke Bol of the Netherlands in 51.70 seconds, ahead Shamier Little of the United States in 52.80 seconds and Rushell Clayton of Jamaica in 52.81 seconds.
The women's 400 metres hurdles at the 2024 Summer Olympics was held in four rounds at the Stade de France in Paris, France, from 4 to 8 August 2024. This was the eleventh time that the women's 400 metres hurdles was contested at the Summer Olympics. A total of 40 athletes were able to qualify for the event by entry standard or ranking.
