It will be the first time since 1977 in London that two international summits will be held at the same time in the same city. Security experts say it will be a security challenge that no American city has ever had to face. Planning is likely to focus on the possibility of violent demonstrations.
Chicago does not want to risk a repeat of 1999's "Battle of Seattle," when thousands of people protested the World Trade Organization meeting.
"There is a lot at stake, and therefore there will be a lot of dedicated and smart people directing their attention in how to make this event a success, and making it a success means making the event uneventful," said Loyola University's Dr. Arthur Lurigio.
Hosting the G8 and NATO summits at the same time means bringing together leaders from the world's most powerful countries in terms of wealth and militaries. Security is expected to unprecedented.
"I would characterize it as a multi-layered security enterprise that will require a year-long planning process," said Lurigio.
Mayor Rahm Emanuel lobbied his old boss, President Barack Obama, hard to land the summit.
"It's an opportunity for the City of Chicago, economically but also as a message internationally, why Chicago is a city that's on the move. That if you're thinking of investing, Chicago is a place to invest," Emanuel said.
Knowing the security challenges financially, Emanuel is hoping to get private donors to help supplement the city's resources.
Politically, the summits are a big risk if security fails. No one will forget the 1968 Democratic convention even as the city redeemed itself with a successful 1996 convention.
"The scope of the Democratic convention is nowhere near the scope of the G8 and NATO summits," said Lurigio.
Experts say local, state, and federal law enforcement agencies are coordinating now for next year's meetings.
While Mayor Emanuel says Chicago will benefit economically, he also knows, if there are any security failures, he and his police Superintendent Garry McCarthy will get the blame, so a lot is a stake.