Readers of this newspaper may have stared in disbelief last week at a news story out of Central Islip, N.Y., about a couple convicted of holding two housekeepers as slaves. For years, the millionaire couple beat and otherwise abused the two servants, who are not U.S. citizens.

But the case of Mahender Sabhnani and his wife, Varsha, is just one example of an underground scourge of slavery that covers the globe. As we said last March, slavery did not end with the Civil War, as most Americans believe. By some estimates, 17,500 people enter the United States each year as slaves. Worldwide, as many as 12 million people are held in bondage. The State Department reports as many as 800,000 people are taken across national borders by criminal gangs each year. That means slavery is a bigger problem today than ever before in recorded history.

Every now and then, the problem bubbles to the surface, as it did in Central Islip. Or as it did in Georgia recently, where a woman, her deputy sheriff husband and his father, who is a county magistrate judge, were indicted on nine counts related to human trafficking. They allegedly lured an Indian national to come to the United States under false pretenses, then forced her to work for free, threatening her with jail or deportation if she didn't cooperate.

In recent weeks, a federally funded study showed that children are being sold for sex in the wake of Hurricane Katrina in New Orleans and Baton Rouge. Much of the world's slavery problem is related to the sex industry, but some experts say that for every one sex slave, there are 15 people in bondage for labor. The State Department also reports that the pressure to produce ethanol from sugar cane has led to an increase in slavery in Brazil.

The problem itself is appalling, but it is compounded by the general ignorance toward its existence. Few Americans come in contact with slaves on a daily basis, making it difficult for people to believe the problem runs rampant. But the victims seldom are allowed a voice. They are uneducated and virtually never speak the language of the country in which they are forced to work.

Maybe criminal trials, such as the one in New York, will help raise awareness.