The men's 400 metres hurdles at the 2004 Summer Olympics as part of the athletics program were held at the Athens Olympic Stadium from August 23 to 26. There were 35 competitors from 24 nations. The event was won by Félix Sánchez of the Dominican Republic, the nation's first medal in the men's 400 metres hurdles. Silver went to Danny McFarlane of Jamaica, returning to the podium in the event for the first time since 1992. Naman Keïta's bronze was France's first medal in the event in over 100 years; the last Frenchman to medal in the long hurdles was Henri Tauzin in 1900. The United States' five-Games gold medal streak ended; for only the second time in the history of the event, Americans competed but won no medals.
The women's 400 metres hurdles at the 2004 Summer Olympics as part of the athletics program were held at the Athens Olympic Stadium from August 21 to 25.
Brigitte Heike Meissner is a retired German athlete. She competed mainly in the 400 metres hurdles, but also spent two seasons specializing in the 800 metres. Notable achievements include a silver medal at the 2002 European Championships, medals in 4 x 400 metres relay at the 1994 European Championships and the 1997 World Indoor Championships and a fourth place at the 1995 World Championships.
The women's 4 × 400 metres relay races at the 2000 Summer Olympics as part of the athletics program were held on Friday, 29 September and Saturday, 30 September. The first two in each heat and the next 2 fastest overall advanced to the final.
Niger sent five athletes, their second largest contingent ever, equalling the most sports in which they have participated. to compete at the 2008 Summer Olympics in Beijing, China. It was Niger's 10th Olympics; their only medalist has been Issaka Dabore, in boxing, at the 1972 games.
The Women's 400 metre Hurdles at the 2000 Summer Olympics as part of the athletics programme were held at Stadium Australia on Sunday 24 September, Monday 25 September and Wednesday 27 September 2000.
Comoros competed at the 2012 Summer Olympics in London, England, which was held from 27 July to 12 August 2012. The country's participation at London marked its fifth appearance in the Summer Olympics since its début at the 1996 Summer Olympics. The delegation included two track and field athletes: Maoulida Darouèche and Feta Ahamada, and one swimmer, Ayouba Ali Sihame, all three qualified for the Games through wildcard places. Ahamada was selected as the flag bearer for the opening ceremony and Darouèche held it at the closing ceremony. Ahamada won her heat in the preliminary round of the women's 100 metres but was eliminated in the heat stages, while Darouèche and Sihame did not advance beyond the first round of their respective events.
The African island nation of São Tomé and Príncipe competed at the 2012 Summer Olympics in London, held from 27 July to 12 August 2012. This was the nation's fifth appearance at the Olympics since its debut in 1996. Two track and field athletes, Christopher Lima da Costa and Lecabela Quaresma were selected to the team by wildcard places, without having qualified at any sporting event. Quaresma was selected as flag bearer for the opening and closing ceremonies. Neither of the two athletes progressed beyond the first round of their respective events.
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 400 metres hurdles at the 2017 World Championships in Athletics was held at the London Olympic Stadium on 7−8 and 10 August.
The men's 400 metres hurdles event at the 2020 Summer Olympics took place between 30 July and 3 August 2021 at the Olympic Stadium. 36 athletes from 26 nations competed.
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 400 metres hurdles competition of the athletics events at the 2019 Pan American Games will take place between the 6 and 8 of August at the 2019 Pan American Games Athletics Stadium. The defending Pan American Games champion is Shamier Little from the United States.
The men's 400 metres hurdles competition of the athletics events at the 2019 Pan American Games will take place between the 6 and 8 of August at the 2019 Pan American Games Athletics Stadium. The defending Pan American Games champion is Jeffery Gibson from the Bahamas.
The women's 100 metres hurdles competition of the athletics events at the 2019 Pan American Games will take place between the 7 and 8 of August at the 2019 Pan American Games Athletics Stadium. The defending Pan American Games champion is Queen Harrison from the United States.
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 hurdles at the 2022 Commonwealth Games, as part of the athletics programme, took place in the Alexander Stadium on 4 and 6 August 2022.
The women's 400 metres at the 2022 European Athletics Championships took place in three rounds at the Olympiastadion in Munich, Germany, from 15 to 17 August 2022.
The women's 400 metres hurdles at the 2022 European Athletics Championships took place in three rounds at the Olympiastadion in Munich, Germany, from 17 to 19 August 2022.
The women's 400 metres hurdles competition of the athletics events at the 2023 Pan American Games was held on November 1 and 3 at the Julio Martínez National Stadium of Santiago, Chile.
