The men who buy sex are your neighbors and colleagues. A new study reveals how the burgeoning demand for porn and prostitutes is warping personal relationships and endangering women and girls.

Men of all ages, races, religions, and backgrounds do it. Rich men do it, and poor men do it, in forms so varied and ubiquitous that they can be summoned at a moment’s notice.

And yet surprisingly little is known about the age-old practice of buying sex, long assumed to be inevitable. No one even knows what proportion of the male population does it; estimates range from 16 percent to 80 percent. “Ninety-nine percent of the research in this field has been done on prostitutes, and 1 percent has been done on johns,” says Melissa Farley, director of Prostitution Research and Education, a nonprofit organization that is a project of San Francisco Women’s Centers.

A clinical psychologist, Farley studies prostitution, trafficking, and sexual violence, but even she wasn’t sure how representative her results were. “The question has always remained: are all our findings true of just sex buyers, or are they true of men in general?” she says.

In a new study released exclusively to NEWSWEEK, “Comparing Sex Buyers With Men Who Don’t Buy Sex,” Farley provides some startling answers. Although the two groups share many attitudes about women and sex, they differ in significant ways illustrated by two quotes that serve as the report’s subtitle.

One man in the study explained why he likes to buy prostitutes: “You can have a good time with the servitude,” he said. A contrasting view was expressed by another man as the reason he doesn’t buy sex: “You’re supporting a system of degradation,” he said.

And yet buying sex is so pervasive that Farley’s team had a shockingly difficult time locating men who really don’t do it. The use of pornography, phone sex, lap dances, and other services has become so widespread that the researchers were forced to loosen their definition in order to assemble a 100-person control group.

“We had big, big trouble finding nonusers,” Farley says. “We finally had to settle on a definition of non-sex-buyers as men who have not been to a strip club more than two times in the past year, have not purchased a lap dance, have not used pornography more than one time in the last month, and have not purchased phone sex or the services of a sex worker, escort, erotic masseuse, or prostitute.”

Many experts believe the digital age has spawned an enormous increase in sexual exploitation; today anyone with access to the Internet can easily make a “date” through online postings, escort agencies, and other suppliers who cater to virtually any sexual predilection. The burgeoning demand has led to a dizzying proliferation of services so commonplace that many men don’t see erotic massages, strip clubs, or lap dances as forms of prostitution. “The more the commercial sex industry normalizes this behavior, the more of this behavior you get,” says Norma Ramos, executive director of the Coalition Against Trafficking in Women (CATW).

The ordinariness of sex buyers is suggested by their traditional designation as “johns,” the most generic of male names. “They’re the cops, the schoolteacher—the dignified, respected individuals. They’re everybody,” says a young woman who was trafficked into prostitution at the age of 10 and asked to be identified as T.O.M.

Equally typical were the men in Farley’s study, who lived in the Boston area and ranged from 20 to 75, with an average age of 41. Most were married or partnered, like the majority of men who patronize prostitutes.

Overall, the attitudes and habits of sex buyers reveal them as men who dehumanize and commodify women, view them with anger and contempt, lack empathy for their suffering, and relish their own ability to inflict pain and degradation.

Farley found that sex buyers were more likely to view sex as divorced from personal relationships than non buyers, and they enjoyed the absence of emotional involvement with prostitutes, whom they saw as commodities. “Prostitution treats women as objects and not … humans,” said one john interviewed for the study.

In their interviews, the sex buyers often voiced aggression toward women, and were nearly eight times as likely as non buyers to say they would rape a woman if they could get away with it. Asked why he bought sex, one man said he liked “to beat women up.” Sex buyers in the study committed more crimes of every kind than non buyers, and all the crimes associated with violence against women were committed by the johns.

Prostitution has always been risky for women; the average age of death is 34, and the American Journal of Epidemiology reported that prostitutes suffer a “workplace homicide rate” 51 times higher than that of the next most dangerous occupation, working in a liquor store