The rallies started at five different locations around the city, eventually converging at the Art Institute on Michigan Avenue, where a reception took place Monday evening for members of the financial futures trading industry.
An estimated 3,000 people took part in the protest, according to Chicago police. The protesters were agitating for better education, affordable housing, and more jobs.
The demonstrators targeted two financial organizations, the Futures Industry Association and the Mortgage Bankers Association, which are having conferences in Chicago this week.
Many protesters were union members. Others were fighting foreclosure, war, poverty, and unemployment. They converged from five rallying points across the city including the Board of Trade and Daley Plaza.
"We are the 99 percent! We are the 99 percent!" the crowd chanted.
"I'm tired of the rich getting richer and the poor getting poorer," one demonstrator told ABC7.
"People need jobs. My son was laid off two and a half years ago. He has two masters and he can't find a job," said Yvonne Wells, protester.
Some activists came dressed as Robin Hood in kayaks. Others arrived by stroller.
"This is their future. They're the ones that are going to have to live with the mess we're making, they're going to have to find solutions to these problems," said Autumn Hamer, mother and protester.
"I'm just a grandma wanting to make things better," said Sue Smit, protester.
Protestors chanted "shame on you" from below, while those attending the reception watched from above.
"No one feels targeted. This is a sad, sad time and somehow people need to come together. Instead of dividing, we need to unite," said Mark Abrams, who works in the mortgage industry.
With their message delivered, organizers said it's now up to Wall Street and Washington to listen.
"When there's this many people being forced out of their homes, this many unemployed and they're this angry, it's not hard to put together a demonstration like this," said Adam Kader, protest organizer.
Police cited two dozen people for staging a sit-in on the street.
The Occupy Chicago group plans to continue its daily demonstrations in the financial district Tuesday. That'll be day 18 for them. Other groups plan smaller demonstrations about jobs, foreclosure and schools outside the mortgage bankers and futures traders meetings in the next few days.