The World Championships start in Doha on Friday with the globe's best athletes travelling to Qatar.
Here, we looks at the international athletes to watch at the Khalifa International Stadium.
The 400m Olympic champion has not lost a race for two years and is expected to claim her first 400m world title in Doha having won a silver in 2015 and missing out on the podium in 2017.
She has been in imperious form and it would be a shock not to see the 25-year-old win.
In a huge boost to Dina Asher-Smith's 200m hopes that Miller-Uibo will not run in that event because the schedule is too tight.
Sky Bet odds: At 2/5 favourite, Miller-Uibo heads the betting from 5/2 shot Salwa Eid Naser while next in the running is Aminatou Seyni (6/1) (click here to bet).
When will she compete? 400m. Heats: 16:20 BST, Monday, 30 September. Semi-finals: 18:50 BST, Tuesday, 1 October. Final: 21:50 BST, Thursday, 3 October
The charismatic Norwegian hit headlines for his memorable reaction to winning the 400m hurdles title at the World Championships in London two years ago.
Karsten Warholm's reaction to winning gold is absolutely priceless. pic.twitter.com/y62qfoRGMd
— BBC Sport (@BBCSport) August 9, 2017
Since then he's continued his dominance and produced the second-fastest performance of all time at the Diamond League final last month.
He ran 46.92 seconds to become just the third man to crack the 47-second barrier.
THAT WAS ABSOLUTELY INCREDIBLE.
— Eurosport UK (@Eurosport_UK) August 29, 2019
Karsten Warholm clocks the second-fastest time in HISTORY pic.twitter.com/uIVJ1VrAIF
Warholm will be seen as the favourite for the title even if Rai Benjamin and home hero Abderrahman Samba will challenge him for gold in Doha.
Sky Bet odds: Warholm is the clear 8/11 favourite ahead of Abderrahman Samba of Qatar (9/4) and USA's Rai Benjamin (5/2) (click here to bet).
When will he compete? 400m hurdles. Heats: 18:30 BST, Friday, 27 September. Semi-finals: 16:05 BST, Saturday, 28 September. Final: 20:40 BST, Monday, 30 September
The favourite for the 100m comes into the championships under a cloud.
He has been cleared to run after the US Anti-Doping Agency withdrew its case after the 23-year-old was charged with missing three drugs tests and faced an automatic one-year ban.
Coleman, who came second behind Justin Gatlin in the 100m two years ago, has always denied the charge.
The American is the fastest man in the world this year with a time of 9.81 and has won his last five races, including at the US trials, while he's broken 10 seconds on all but one of his six outings.
Sky Bet Odds: Christian Coleman is odds-on favourite at 4/7 while his main challengers are Justin Gatlin (4/1), Andre De Grasse (10/1) and Yohan Blake (12/1) (click here to bet).
When will he compete? 100m. Heats: 16:05 BST, Friday, 27 September. Semi-finals: 16:45 BST, Saturday, 28 September. Final: 20:15 BST, Saturday, 28 September
200m. Heats: 15:05 BST, Sunday, 29 September. Semi-finals: 18:50 BST, Monday, 30 September. Final: 20:40 BST, Tuesday, 1 October
The Jamaican remains the biggest threat to Dina Asher-Smith in the 100m - even if the Briton did beat her in the recent Diamond League final.
World championship victories in 2009, 2013 and 2015 underlines her lasting quality and, at 32, she could become the oldest woman to win a sprint world title.
The double Olympic champion, having taken the 2008 and 2012 100m titles, clocked her fastest time this year of 10.73 seconds in June while she also managed an impressive 10.78 when defeating Asher-Smith at the London Anniversary Games.
Fraser-Pryce will also take part in the 200m although that event hasn't brought her quite so much success having managed one world title in 2013 - when completing the sprint double - and silver at the London 2012 Olympics.
Sky Bet Odds: Fraser-Pryce is 13/8 favourite in the 100m ahead of Elaine Thompson (15/8) and Asher-Smith (9/4) (click here to bet) behind but she's third in the betting at 13/2 in the 200m (click here to bet).
When will she compete? 100m. Heats: 14:30 BST, Saturday, 28 September. Semi-finals: 19:20 BST, Sunday, 29 September. Final: 21:20 BST, Sunday, 29 September
200m. Heats: 15:05 BST, Monday, 30 September. Semi-finals: 19:35 BST, Tuesday, 1 October. Final: 20:35 BST, Wednesday, 2 October
The defending heptathlon champion, who also holds the European and Olympic title, remains the one to beat.
Katarina Johnson-Thompson is pushing her close but Thiam remains ahead of all challengers so far.
The 25-year-old beat Johnson-Thompson by 57 points at the Europeans in Berlin last year and has been just out of reach.
Sky Bet Odds: Thiam is the 4/11 favourite ahead of Great Britain's KJT (9/4) while next in the running is 16/1 shot Ivona Dadic (click here to bet).
When will she compete? Heptathlon day one: 15:05 BST, Wednesday, 2 October. Day two: 16:15 BST, Thursday, 3 October