grover Cleveland

Can you say image problem? For the first time in the more than 70 years that Gallup has been measuring the popularity of unions, in 2009 more than half the public didn't approve of them. The current showdowns have plenty of precedent when it comes to transformative moments for organized labor.

Labor Day signals the end of summer and the start of the school year, but it's also is a moment to consider America's workers and the long -- and continuing -- struggle for employee rights. Our photo gallery provides a look at images of workers, past and present.