WHAT: Selection of host city for 2020 Summer Olympics.
WHERE: Buenos Aires, Argentina.
VENUE: Hilton Hotel.
WHEN: Saturday, Sept. 7.
THE CANDIDATES: Istanbul, Madrid and Tokyo.
WHO DECIDES: The International Olympic Committee.
THE MEETING: 125th IOC Session.
THE VOTE: IOC members vote by secret ballot until one city receives a simple majority. City receiving fewest votes is eliminated after each round. Maximum number of rounds will be two.
HOW MANY: IOC has 103 members. President Jacques Rogge chooses not to vote and members from the three bid countries don't vote while their city is still in contention. Spain has three IOC members, Japan and Turkey have one each.
FIRST ROUND: If all members attend, 97 eligible to vote, meaning 49 votes needed for victory. If election goes to second round, member or members from country eliminated in first ballot can vote in second.
PRESENTATIONS: Each city will make 45-minute final presentations, with additional 15 minutes for questions and answers.
THE ORDER: Istanbul, Tokyo and Madrid.
THE BALLOT: Voting begins at 3:45 p.m. local time (2:45 p.m. EDT).
THE ANNOUNCEMENT: Ceremony starts at 5 p.m. local time (4 p.m. EDT). Rogge will open sealed envelope and announce winner.