The remaining 16 teams progress to the first knockout round, which is followed by quarter-finals, semi-finals and the final.
Qatar were the first team knocked out of the World Cup, to the embarrassment of the hosts. Defending champions France were the first team to guarantee their place in the knockout rounds.
What are the group standings?
What does each team need to progress to the last 16?
In Group A
Ecuador-Senegal (29 November, 3pm)
Netherlands-Qatar (29 November, 3pm)
Qatar were the first team knocked out of the World Cup. Netherlands must win or draw to qualify and can lose and still qualify if Ecuador beat Senegal. Ecuador must win or draw to go through but could still qualify if they lose and Netherlands are beaten by Qatar. Senegal must win to qualify but are still in contention if they draw and Qatar beat the Netherlands.
In Group B
Wales-England (29 November, 7pm)
Iran-USA (29 November, 7pm)
England go through with either a win or a draw against Wales. If they lose, they are still likely to qualify on goal difference. Wales must win to reach the knockouts. Iran will definitely go through if they beat the USA and could go through with a draw as long as Wales do not beat England. The USA are through if they beat Iran, out if they lose or draw.
In Group C
Saudi Arabia v Mexico (30 November, 7pm)
Poland v Argentina (30 November, 7pm)
Poland go through with a win or a draw but are out if they lose and Saudi Arabia win. Should Poland lose and the Saudis draw, it'll come down to goal difference, as it will if Poland lose and Mexico win. If Argentina win they go through, but a draw would be enough if there's no winner in the other match. A draw and a Saudi victory would end Argentina's World Cup, while a draw combined with a Saudi loss would mean the group is decided on goal difference. Lose and Argentina are out. Saudi Arabia will go through if they win and will go out if they lose. A draw would also send them through if Poland beat Argentina but draws in both games mean they are out. It'll be down to goal difference if Argentina beat Poland and Saudi Arabia draw. Mexico must win. If Poland also win, Mexico are through. If Poland draw, or if Argentina win it'll be down to goal difference.
In Group D
Tunisia-France (30 November, 3pm)
Australia-Denmark (30 November, 3pm)
France are through. Australia will go through if they win. If they draw, they'll still go through unless Tunisia beat France. Denmark will go through with a win, unless Tunisia beat France, in which case it'll be down to goal difference. Tunisia caa still theoretically go through if they beat France and Denmark do not lose to Australia.
In Group E
Japan-Spain (1 December, 7pm)
Costa Rica-Germany (1 December 7pm)
Spain top the standings with four points and now need only a draw in their final Group E game against Japan to progress. A win would send them through to the knockout round in first place. Germany need to win against Costa Rica on Thursday and their hopes then depend on Japan losing. If Japan draw it would come down to goal difference or goals scored by Germany and Japan. If Japan beat Spain, they're through. They would also go through if both remaining matches end with a draw, but they're out if they lose to Spain or if they draw with Spain and Costa Rica beat Germany. Costa Rica can still qualify if they beat Germany. Even if they draw, they would go through as long as Spain beat Japan. But if Spain lose then goal difference will apply. A draw in both games or a defeat means Costa Rica are going home.
In Group F
Croatia-Belgium (1 December, 3pm)
Canada-Morocco (1 December, 3pm)
Croatia need only a draw in their final game against third-placed Belgium, who are a point behind after losing to Morocco, to guarantee a knockout spot. Belgium must beat Croatia to stay in the competition. Morocco can guarantee their progress by beating Canada, who are now out.
In Group G
Serbia-Switzerland (2 December, 7pm)
Cameron-Brazil (2 December, 7pm)
Brazil lead the group on six points and have already qualified after their second consecutive win, against Switzerland. A draw or a win would see them go through as group winners.
A win for Switzerland, who are second on three points, against Serbia would see them also qualify, though a point would also be enough if Cameroon failed to beat Brazil. A point might also be enough if Cameroon beat Brazil but by only a goal as they would be level on points and goal difference, so the tie-breaker would be on goals scored. Switzerland currently have one goal to their name and Cameroon have three, so that means that Switzerland would need to draw at least 4-4 for that to be a possibility. If Switzerland lose, they are out.
Cameroon and Serbia, on one point each, both need to win to stand any chance of going through, with the other result going their way.
In Group H
South Korea-Portugal (2 December, 3pm)
Ghana-Uruguay (2 December, 3pm)
Group H is similar to Group G in that Portugal are already through with six points and will top the group should they get a draw or a win against South Korea.
Ghana, in second on three points, will guarantee progress with a win against Uruguay, though a point will be enough if South Korea fail to beat Portugal. It might also be enough if South Korea beat Portugal but only by a goal, as both teams would be level on goal difference, but Ghana potentially ahead on goals scored. This is all obviously dependent on how many goals each team scores in those final games. If Ghana lose, they are out.
South Korea and Uruguay, on one point each, both need to win to have any chance of progression, with the other result going their way.
What is the knockout schedule?
Saturday, December 3
Match 49 - Winner of Group A vs Runner-up in Group B, 3pm
Match 50 - Winner of Group C vs Runner-up in Group D, 7pm
Sunday, December 4
Match 52 - Winner of Group D v Runner-up in Group C, 3pm
Match 51 - Winner of Group B v Runner-up in Group A, 7pm
Monday, December 5
Match 53 - Winner of Group E v Runner-up in Group F, 3pm
Match 54 - Winner of Group G v Runner-up in Group H, 7pm
Tuesday, December 6
Match 55 - Winner of Group F v Runner-up in Group E, 3pm
Match 56 - Winner of Group H v Runner-up in Group G, 7pm
Friday, December 9
QF1 - Winner of Match 53 v Winner Match 54, 3pm
QF2 - Winner of Match 49 v Winner Match 50, 7pm
Saturday, December 10
QF3 - Winner Match 55 v Winner Match 56, 3pm
QF4 - Winner Match 51 v Winner Match 52, 7pm
Tuesday, December 13
SF1 - Winner of QF1 v Winner QF2, 7pm
Wednesday, December 14
SF2 - Winner QF3 v Winner QF4, 7pm
Saturday, December 17
Match 63, 3pm
Sunday, December 18
Lusail Stadium, 3pm