Carlos Perez feels invisible. A janitor for 13 years at a downtown Chicago commercial building, his shift starts at 5 p.m. and runs through midnight.  But Perez and his colleagues are tired of working in the shadows.

Their union, Service Employees International Union Local 1, which represents about 15,000 janitors who clean Chicago's buildings and offices, began negotiations this week for a new contract with property managers and contractors.

The current agreement expires April 5.

Erica Hade, a spokeswoman for Local 1, says the union has a healthy relationship with members of the Building Owners and Managers Association, and believes the workers will secure a good contract.

Union members organized a rally Sunday in Chicago to draw attention to the negotiations, which include .

"We believe that our relationship with BOMA is a partnership," Hade says, "we're not going to get the economy back on track if we don't protect the jobs for everyday people." But, she concedes, "everyone knows the context we're working with."

A BOMA spokesman declined to discuss details of the negotiations.

"We are evaluating the needs of our hardworking janitors and remain wholly-committed to participating in amicable negotiations.  It is our hope that we arrive at a positive conclusion for all parties involved," the spokesman said via e-mail.

The average salary for a downtown janitor is about $1,950 a month, according to Hade. Suburban janitors make slightly less. Perez and about 200 hundred other janitors spent Thursday in Schaumburg also rallying there for better conditions.

One owner of a non-union janitorial company says she expects the negotiations will be difficult, and could benefit companies like hers.

"People are trying to hold onto a McDonald's job," says Jean Watkins, who runs the 15-person Easyway Janitorial Services out of her South Side home. Watkins finally secured her first downtown contract cleaning a residential building in the Gold Coast last year. She has been in business since 2000.

She says building owners are looking for any way they can save a buck. And while Watkins supports unionized workers - she was represented before going into business for herself - these are lean times and the name of the game is survival.

"If they get rid of them I will be in line for the contract," she said.

Perez said while times are tough, they need to press for better wages and benefits now because their new contract will run through 2011.    "I am still making 2008 money," Perez says, "if we get a fair contract we'll be able to pay 2009 prices, maybe."    "I'm a very optimistic person," he says.