Anne Viensouk Keothavong (born 16 September 1983) is a British former tennis player. In her career, she won a total of 28 titles on the ITF Women's Circuit, and reached a career-high singles ranking of world No. 48 (achieved February 2009). She also reached the semifinals of six WTA International tournaments, and the semifinals of one Premier tournament. Keothavong was British No. 1 and in 2009 became the first British player to make the WTA top 50 since 1993. In April 2001, aged 17, she became, until Katie Swan in 2016, the youngest player ever to play in the Fed Cup for the British team, and she is second (alongside Elena Baltacha) to Virginia Wade's record for most Fed Cup ties played for the Great Britain with 39.

Keothavong announced her retirement on 24 July 2013. After that, she became a member of BT Sport's tennis coverage team, alongside Martina Navratilova and fellow British ex-number one Sam Smith. In 2017, Keothavong became Fed Cup captain for Great Britain, leading the team to win all four ties played in the Europe/Africa Zone Group I. She continued as captain for the 2018 and 2019 Fed Cup, winning promotion in April 2019 to World Group II for the first time in 26 years.

Early and personal life Keothavong was born in Hackney in London, to parents who had fled from their war-torn home country of Laos in the 1970s. Her father, Somsak, encouraged her to play short tennis from an early age. Her mother's name is Vathana and she has two brothers: James, who is a tennis umpire, and Mark. She also has a sister, Lena. Keothavong attended Kingsland Secondary School in Hackney. At the age of seven, she took up tennis at Hackney Downs and Highbury Fields. Her preferred surface was hardcourt.

Keothavong married Andrew Bretherton, a corporate lawyer, on 28 February 2015. They have a son and a daughter.

Career Junior (1996–2001) Keothavong played her first match on the ITF Junior Circuit in February 1996, at age 12, and her last in August 2001. In singles, she won one title at the LTA Junior International Tournament – Bisham Abbey where she beat compatriot Elena Baltacha in the final. She also reached a total of three semifinals (one of which was at the 2001 Wimbledon Championships where she was beaten by Dinara Safina, the future world number one, who like Keothavong, went on to reach a higher ranking in seniors than in juniors) and ten quarterfinals.

In junior doubles, she won one tournament, the 13th Salik Open, and lost in the final of two others: the LTA International Junior Tournament – Bisham Abbey and the 11th Malaysian International Junior Championships. All three of these were in 1999 and all three were partnering Elena Baltacha.

1998–2001 Keothavong played her first professional match on the ITF Women's Circuit in April 1998, at age 14, when she fell in the first round of qualifying for a $10k tournament in Birmingham. That year she played only two more matches (in the qualifying tournaments for $10k events in Hatfield, Hertfordshire and Felixstowe) and lost both of them. She finished the year without a world ranking.

During May 1999, Keothavong played in a total of five ITF tournaments with her best result being in the $10k event in Sunderland where she won three matches to qualify and then reached the second round. In the other four events, she either lost in the first round or qualifying stages. Her final ranking of the year was world No. 702.

In 2000, Keothavong played ten ITF events, losing in the qualifying stages in one, round one in three others, the second round four times (once as a lucky loser) and the quarterfinal in the $50k tournament in Cardiff. The other tournament she entered was the qualifying event for Wimbledon in which she participated courtesy of a wildcard. She beat Eva Martincová in round one of qualifying before losing to Yuka Yoshida. She improved her ranking to world No. 377.

2001 started well for Keothavong; in her first tournament of the year she won the title by beating compatriot Emily Webley-Smith in the quarterfinals and Elodie Le Bescond in the final. She then reached the quarterfinals of her next tournament, the $10k event in Tipton. In February, she reached the semifinals in Sutton, London ($25k) as a qualifier. She played in the Fed Cup for the first time in April and lost all three of her singles rubbers in straight sets. In June, she was given wildcards into the qualifying draws for the Birmingham Classic (where she was beaten in the first round of qualifying) and the Eastbourne International (where she reached the second round of qualifying) and the main draw of Wimbledon. She faced Janet Lee in round one and lost. In September and October, she reached three ITF quarterfinals (one $50k, one $25k and one $10k) and one semifinal ($25k). Her ranking at the end of 2001 was No. 268.

2002 She started slowly the new season; she played in 13 ITF tournaments and did not pass the second round in any. In June, she was given a wildcard into the qualifying draw of Birmingham where she lost in round one. She also attempted to qualify for the Eastbourne International and was again defeated in the first round. In the main draw of Wimbledon, she lost in round one to Virginie Razzano. Immediately after Wimbledon she headed to Felixstowe to participate in a $25k tournament where she reached the quarterfinals. In August and September, she reached four consecutive ITF finals, winning three. She won the first in Bath beating Hannah Collin. She was victorious in London when she defeated Yvonne Doyle but lost in the third final in Glasgow to Selima Sfar. In Sunderland, her fourth consecutive final of August and September, she won by again beating Hannah Collin. She competed in three more $25k tournaments that year and reached the semifinals in two of them. Her final ranking of 2002 was 233.

2003 The first tournament of 2003 for her was the qualifying event for the Hobart International where she lost to Tiffany Dabek in the first round. Keothavong then headed to the Australian Open in order to attempt to qualify and she again lost in the first round to Sandra Klösel. After this she headed to the ITF Circuit and won the $25k event in Belfort by defeating Nathalie Viérin in the final. Two weeks later she reached the quarterfinals of a $25k in Redbridge, London and the week after that lost in the final of yet another $25k event in Ostrava. In March, she reached the quarterfinals of Redding, California ($25k) and in April she headed to Portugal to represent Great Britain in the Fed Cup. She won two of her four singles rubbers. May saw Keothavong reach the second round of qualifying for the French Open. In her next tournament (Surbiton $25k), she reached the semifinals but had to withdraw before the match. Keothavong did not compete again until mid-June when she was given a wildcard into the main draw of the Eastbourne International where she was defeated by Japanese veteran, Ai Sugiyama. A second consecutive wildcard gave her entry into the main draw of the Wimbledon Championships where she had to withdraw during her first-round match against Katarina Srebotnik with the score at 2–6, 0–4. Reaching the final round of qualifying for the US Open, she lost to Maureen Drake and had no more notable results that year which she finished with a singles ranking of 177.

2004 The season began well for Keothavong as she started off by qualifying for the Tier-V Hobart International, beating Kaia Kanepi along the way. In the first round she faced world No. 69, Rita Grande, but was beaten. This was followed by an attempt to qualify for the Australian Open. She was beaten in the first round of qualifying by Stephanie Gehrlein. In February, she reached the quarterfinals of ITF events in Sunderland ($25k) and Saint Paul ($50k), beaten by Lisa Stanciute and Jill Craybas, respectively. The next month, she won the sixth ITF title of her career by beating Mashona Washington in the final of the $25k event in Redding. In late April and early May, she represented Britain in the Fed Cup and won all three of her singles rubbers, but lost her one and only doubles match with partner, Elena Baltacha, before going on to lose in the first round of qualifying for the French Open to Květa Peschke.

In the run up to Wimbledon, Keothavong was given a wildcard into the main draw of the Birmingham Classic where in the first round she faced world No. 60, Marta Marrero, who she managed to beat in three sets. Keothavong came up against world No. 56, María Sánchez Lorenzo (the 16th seed) in the second round and lost in three sets. She headed to the main draw of the Tier-II Eastbourne International and faced No. 8 seed, Magdalena Maleeva, and was again beaten in three sets. A wildcard granted Keothavong entry to the main draw of Wimbledon for the fourth consecutive year where she won her first-round match, beating Nicole Pratt, the world No. 41, in a performance assisted by a rain delay when Keothavong was 3–1 down in the first set. The eventual champion, Maria Sharapova, beat her in the second round. Keothavong played in two $50k events in the United States reaching the second round in one and the quarterfinals in the second, in Lexington, Kentucky where she had to withdraw due to sustaining serious ligament damage with the score at 5–7, 3–5. She did not play again that year and finished with a WTA ranking of No. 175.

2005 Keothavong recovered well from her injury and returned to action ahead of schedule in March at the $10k tournament in Sunderland where she suffered a three-set first-round defeat by Verdiana Verardi. She then immediately reached three successive $10k finals; the first in Bolton and the second two in Bath. She won the first two by beating Veronika Chvojková and Claire Peterzan, respectively, and lost the third to compatriot, Melanie South. The first of the two tournaments in Bath was also the only time Keothavong competed with her sister Lena in doubles on the ITF Circuit. They reached the quarterfinals together. In late April, Keothavong competed in the Fed Cup and helped Britain avoid relegation from the Africa/Europe Zone Group I by beating Caroline Wozniacki to help Britain beat Denmark. This meant that although they lost ties against Serbia and Montenegro and Slovenia, they avoided a place in the relegation play-offs for another year.

In May, Keothavong reached the semifinals of a $25k event in Monzón where she lost to Angelique Kerber. She was then given a wildcard into the main draw of the Birmingham Classic but she lost to Laura Granville in the first round. This was followed by a wildcard into the Eastbourne qualifying tournament where Arantxa Parra Santonja defeated her in the first round. After this, another wildcard allowed Keothavong entry into the main draw of Wimbledon where she faced Mariana Díaz Oliva in the first round and lost in straight sets.

Keothavong competed on the ITF Circuit for the rest of the year (except when she reached the second round of the Tier-III event, the Bell Challenge, where she lost to Sofia Arvidsson) and won two more titles. The first was in Nottingham where she beat Karen Paterson in a three-set final, and the second was a $25k tournament in Lagos where she defeated Maša Zec Peškirič to win the title. She also reached one more $25k final this year, also in Lagos, where she lost to Petra Cetkovská in three sets. Her year-end ranking for 2005 was world No. 239.

2006