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UEFA was allocated thirteen qualifying berths for the 1986 FIFA World Cup, and one place in a play-off, however Italy were the defending champions and qualified automatically, leaving 12.5 spots open for competition between 32 teams.
The 32 teams were divided into 7 groups. The teams would play against each other on a home-and-away basis. The number of teams and spots for each group were as follows:
Groups 2, 3, 4 and 6 had 5 teams each. The group winners and runners-up would qualify.
Groups 1, 5 and 7 had 4 teams each. The group winners would qualify. The runners-up of Groups 1 and 5 would advance to the UEFA Play-offs, while the runner-up of Group 7 would advance to the UEFA / OFC Intercontinental Play-off.
In the Play-offs, the 2 teams would play against each other on a home-and-away basis, with the winner qualifying.