There are other ways of enforced labour as well as slavery, and some are quite close to home. Indentured workers, and poor houses for example, and the company scrip, are slightly less brutal forms of something similar to slavery, as are workers in the penal system. In all of these systems the workers aren't really able to walk away from their "owner". And some of this is fairly recent involving Ikea [4] and Walmart [5].
http://en.wikipedia.org/wiki/Indentured_servant http://en.wikipedia.org/wiki/Company_scrip http://en.wikipedia.org/wiki/Penal_labour [4] http://www.nytimes.com/2012/11/17/business/global/ikea-to-re... [5] http://www.reuters.com/article/2008/09/05/mexico-walmex-idUS...