When FIFA president Sepp Blatter opens the envelopes to reveal the winning names for the two tournaments at the Zurich Messezentrum sometime after 1600 local time (1500 GMT), he will spark a financial, economic and social frenzy that will last in the winning countries for more than a decade.
The value of hosting the World Cups is virtually incalculable and could boost the economies of the winning bidders and of FIFA itself by hundreds of millions of dollars, pounds, roubles, euros or any other currency involved.
Thursday is the culmination of a bidding process that has involved 11 nations with England, Russia and joint bids from Spain/Portugal and Netherlands/Belgium seeking to host the finals in Europe in 2018.
The United States, Japan, South Korea, Qatar and Australia are involved in a separate race for 2022 and by awarding two World Cups so far into the future, FIFA is closing the door on any more World Cup bidding wars for around 10 years when the next contest begins for the 2026 World Cup.
The Netherlands/Belgium campaign team will be the first in action on Thursday when they begin their final presentation to the executive committee at 0900 local time (0800 GMT), followed by Spain/Portugal at 1000 (0900 GMT), England at 1100 (1000 GMT) and Russia at 1200 (1100 GMT).
The executive committee convenes at 1400 (1300 GMT) with the results expected around 1600 (1500 GMT).
Apart from sparking a likely economic boost for the successful candidates, the only other thing certain in Zurich is that the competition for both tournaments is too close to call — with no-one able to predict which way the 22-man executive committee will vote in its secret ballot.