Then last August they heard that the NATO summit was coming to Chicago, bringing in dozens of political leaders and their entourages including U.S. President Barack Obama. There would be added security, street closures and protests.

It was not what the couple had in mind for their big day. Many of their 100 or so guests would be traveling from out of town, and they wanted them to be able to enjoy the city.

They changed the date, marrying instead on a beautiful 70-degree F (21-degrees C) Saturday, April 14.

"It worked out perfectly," said Debbie Sevilis.

Chicago is not used to hosting a major global event, and the summit of the 28-nation military alliance starting on Sunday has residents of America's third-largest city scrambling to get out of the way.

They have changed weddings, made plans to work from home Friday and Monday and are generally fleeing the city in case all hell breaks loose during expected protests.

Some main roads and highways into and out of the city will be closed, buses rerouted and one commuter rail line shut down.

The city's world-class museums such as the Art Institute of Chicago and the Field Museum of natural history will not be open to the public when the world comes calling - although they will host private events for the foreign delegations.

Boeing Co (BA.N), one of several Fortune 500 companies headquartered in Chicago, is allowing employees to work from home on Monday after the company was targeted for a possible protest.

"SAFETY ZONE"

Along Michigan Avenue, the city's main shopping thoroughfare dubbed "The Magnificent Mile," the Crate and Barrel store has prepared an emergency email and phone response system to get messages to employees. Lunch will be provided so employees do not have to leave the store even though the area is teeming with restaurants.

A "safety zone" has been created in the store and they will have extra security, and people to fix any windows broken by protesters.

Store manager Peter Smey said his main concerns are that a protest flash mob will hit the store, there may be a bomb scare at the towering John Hancock building down the street, or that sales will decline if passersby avoid the area.

"In my best opinion, nothing is going to happen and it will be business as usual," Smey said.

The NATO summit is forecast to bring $128.2 million to the city, $3 million in local tax revenues, and nearly 2,200 temporary jobs, according to an economic impact study by the accounting firm Deloitte. Chicago Mayor Rahm Emanuel says there is an intangible benefit to Chicago of the international exposure.

"Quite frankly, I think it (the study) is a joke," said Kelvin Ho, a member of the anti-Wall Street protest movement Occupy Chicago. "If anything, it's going to have a net cost to the city.

Wedding industry planners, for one, said they have seen a downturn in business this month because of the NATO summit, and some have blacked out the weekend altogether. For them, May is a prime wedding month and Saturdays are gold.

"It took a whole weekend away from us," said Anthony Navarro, founder of Liven It Up Events.

Navarro estimated he is losing up to $10,000 in revenue this weekend. But he said it will be busier in July, August and possibly September because couples have pushed back their nuptials.

CONCESSIONS

Not everyone is fleeing NATO. Chris Moon and her fiancé, McAfee Burke, booked the Chicago Cultural Center - the crown jewel of Chicago wedding venues and just a few miles from the NATO summit site - more than a year ago for their wedding on Saturday.

NATO defense ministers will use the venue for their dinner on Sunday night, a day after their wedding.

"Planning a wedding has enough moving parts as it is, so adding the NATO Summit into the mix brought a whole new level of difficulty to the wedding weekend," said Darcey Lohman, a wedding planner for Big City Bride, which is handling the event.

Prospective bride Moon said they have had to make concessions to pull it off amid the summit.

A NATO team needed the hall they had booked for their cocktail hour overlooking one of the city's newest attractions, Millennium Park. Cocktail hour will now take place in a gallery overlooking Michigan Avenue.

The parking garage next to the venue will be closed, so the couple must provide valet parking. They changed the start time of the ceremony to give guests more time to arrive.

Their wedding website offers some advice: "Please allow yourselves ample time to arrive at the venue. There may be rolling street closures due to public protests and the transportation of foreign dignitaries."

Moon said she is confident in the wedding planner and is preparing herself for things not going exactly as she envisioned.

"Of course, I'm nervous. I'm hoping that everything comes together easily," she said.

(Additional reporting by Andrew Stern; Editing by Greg McCune and Xavier Briand)

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