In early June, ABC News correspondent Dan Harris took a three-and-a-half hour flight from New York City to Port Au Prince, Haiti to buy a child slave. Within ten hours of leaving ABC News headquarters in New York City, "Nightline's" hidden cameras captured three separate offers made to Harris for the sale of a ten-year-old child slave. Prices ranged from $150 to $10,000. One broker promised to personally train the child. Another promised a "pretty" girl and offered to provide false adoption documents to allow the child to be taken out of the country. Harris then met and interviewed child slaves and their masters, and explored the dire conditions that drive many rural families to send their children to live in urban households with the often unfulfilled promise of a better life and an education. Finally, he followed the heroic efforts of one mother to retrieve her child from slavery.

E. Benjamin Skinner, the author of A Crime So Monstrous, a new book on modern day slavery (http://www.acrimesomonstrous.com/), joined Harris in Haiti and provided inspiration for the report. Skinner explains that slavery not only continues, but that "today there are more slaves than at any point in human history." Skinner estimates the global number at about 27 million. In Haiti, where the forced servitude of children is technically illegal, Skinner cites an estimated 300,000 children bound to work as domestic laborers under the threat of violence for no pay beyond subsistence - an internationally accepted definition for slavery.

Pastor Jean-Etienne Charles, a local Pentecostal pastor who preaches against child slavery, explains to Harris the wrenching decision parents are forced to make about their children's future: "I do not think that it is because they do not love the child; they love them. But because they think they cannot take care of them, so they turn them [over] to another person. And the other person ensures them that they will take care of the child. But when the child gets into the house, they do not keep their promises. That kid is not free. They ask him to do something, but if the kid refuses to do it, they will beat him - beat him to death."

As part of this report, ABCNews.com will post Web links to several organizations dedicated to the issue of slavery in Haiti and around the globe. Viewers will also be invited to e-mail questions to Benjamin Skinner.

"Nightline" is anchored by Cynthia McFadden, Terry Moran and Martin Bashir. John Donvan and Vicki Mabrey are correspondents. James Goldston is the executive producer. "Nightline" airs weeknights at 11:35 p.m., ET on the ABC Television Network.