Wales have been drawn into the second-tier of Uefa's new Nations League tournament after losing their last 2018 World Cup qualifier.
All 55 European teams are divided into four pots dependant on their rankings, with the top 12 going into League A.
They will play each other home and away from September to November next year.
Going forward, a promotion and relegation system will operate between the leagues - four up, four down - and the second edition of the competition is scheduled to start in September 2020.
The winner will be decided at a tournament between the winners of the four league A groups in June 2019, with semi-finals, a third-place match and a final to be held in one of the finalist countries.
UEFA has introduced the competition to revive international football with more competitive matches and to give nations more chances to play against teams of a comparable standard.
But many fans, players and pundits have expressed some confusion over the idea, particularly as it will run alongside qualifying for the 2020 European Championships.
That process will now begin in March 2019, with countries split into 10 groups of five or six, and the top two teams in each group will qualify for the finals.
The major change, however, is that the final four places will be decided via play-offs between the winners of the 16 Nations League groups in 2018.
Each league - A to D - will have its own play-off competition with single-leg semi-finals and a final to decide who wins the place. The draw for those play-offs will take place in November 2019 and the play-offs themselves will occur in March 2020.
If the winners of a Nations League group have already qualified for Euro 2020 via the qualifying groups, their place in the play-off will go to the next best team in their Nations League group that has not secured a place.
If a league still does not have enough teams for a play-off, as is entirely possible for league A, the places will be filled by the best-ranked teams from the league below.
UEFA Nations League 2018/19:
- League A: Germany, Portugal, Belgium, Spain, France, England, Switzerland, Italy, Poland, Iceland, Croatia, Netherlands.
- League B: Austria, Wales, Russia, Slovakia, Sweden, Ukraine, Ireland, Bosnia-Herzegovina, Northern Ireland, Denmark, Czech Republic, Turkey.
- League C: Hungary, Romania, Scotland, Slovenia, Greece, Serbia, Albania, Norway, Montenegro, Israel, Bulgaria, Finland, Cyprus, Estonia, Lithuania.
- League D: Azerbaijan, Macedonia, Belarus, Georgia, Armenia, Latvia, Faroe Islands, Luxembourg, Kazakhstan, Moldova, Liechtenstein, Malta, Andorra, Kosovo, San Marino, Gibraltar.