Last weekend, Craigslist, the popular provider of Internet classified advertising, halted publication of its "adult services" section. The move followed criticism from law enforcement officials across the country who have accused the site of facilitating prostitution on a massive scale. Of course, selling sex is an old business -- most say the oldest. But as the Craigslist controversy proves, it's also one of the fastest changing. And as a result, most people's perceptions of the sex trade are wildly out of date.

1. Prostitution is an alleyway business.



It once was, of course. In the late 1800s, as Northern cities boomed, the sex trade in America became synonymous with the seedy side of town. Men who wanted to find prostitutes combed alleys behind bars, dimly lit parks and industrial corridors. But today, only a few big cities, such as Los Angeles and Miami, still have a thriving outdoor street market for sex. New York has cleaned up Times Square, Chicago's South Loop has long since gentrified, and even San Francisco's infamous Tenderloin isn't what it used to be.

These red-light districts waned in part because the Internet became the preferred place to pick up a prostitute. Even the most down-and-out sex worker now advertises on Craigslist (or did until recently), as well as on dating sites and in online chat forums. As a result, pimps' role in the sex economy has been diminished. In addition, the online trade has helped bring the sex business indoors, with johns and prostitutes increasingly meeting up in bars, in hotels, in their own homes or in apartments rented by groups of sex workers. All this doesn't mean a john can't get what he's looking for in the park, but he had better be prepared to search awhile.

Although putting numbers on these trends is difficult, the transition from the streets to the Internet seems to have been very rapid. In my own research on sex workers in New York, women who in 1999 worked mostly outdoors said that by 2004, demand on the streets had decreased by half.

2. Men visit sex workers for sex.



Often, they pay them to talk. I've been studying high-end sex workers (by which I mean those who earn more than $250 per "session") in New York, Chicago and Paris for more than a decade, and one of my most startling findings is that many men pay women to not have sex. Well, they pay for sex, but end up chatting or having dinner and never get around to physical contact. Approximately 40 percent of high-end sex worker transactions end up being sex-free. Even at the lower end of the market, about 20 percent of transactions don't ultimately involve sex.

Figuring out why men pay for sex they don't have could sustain New York's therapists for a long time. But the observations of one Big Apple-based sex worker are typical: "Men like it when you listen. . . . I learned this a long time ago. They pay you to listen -- and to tell them how great they are." Indeed, the high-end sex workers I have studied routinely see themselves as acting the part of a counselor or a marriage therapist. They say their job is to feed a man's need for judgment-free friendship and, at times, to help him repair his broken partnership. Little wonder, then, that so many describe themselves to me as members of the "wellness" industry.

3. Most prostitutes are addicted to drugs or were abused as children.



This was once the case, as a host of research on prostitution long ago confirmed. But the population of women choosing sex work has changed dramatically over the past decade. High-end prostitutes of the sort Eliot Spitzer frequented account for a greater share of the sex business than they once did. And as Barnard College's Elizabeth Bernstein has shown, sex workers today tend to make a conscious decision to enter the trade -- not as a reaction to suffering but to earn some quick cash. Among these women, Bernstein's research suggests, prostitution is viewed as a part-time job, one that grants autonomy and flexibility.

These women have little in common with the shrinking number of sex workers who still work on the streets. In a 2001 study of British prostitutes, Stephanie Church of Glasgow University found that those working outdoors "were younger, involved in prostitution at an earlier age, reported more illegal drug use, and experienced significantly more violence from their clients than those working indoors."

4. Prostitutes and police are enemies.



When it comes to the sex trade, police officers have in recent decades functioned as quasi-social workers. Peter Moskos's recent book, "Cop in the Hood: My Year Policing Baltimore's Eastern District," describes how police often play counselor to sex workers, drug dealers and a host of other illegal moneymakers. In my own work, I've found that cops are among the most empathetic and helpful people sex workers meet on the job. They typically hand out phone numbers for shelters, soup kitchens and emergency rooms, and they tend to demonstrate a great deal of sympathy for women who have been abused. Instead of arresting an abused sex worker, police officers will usually let her off with a warning and turn their attention to finding her abusive client.

Unfortunately, officers say it is becoming more difficult to help such women; as they move indoors, it is simply more difficult to locate them. Of course, many big-city mayors embrace this same turn of events, since the rate of prostitution-related arrests drops precipitously when cops can't find anyone to nab. But for police officers, it makes day-to-day work quite challenging.

Officers in Chicago and New York who once took pride in helping women exit the sex trade have told me about their frustration. Abusive men can more easily rob or hurt a sex worker in a building than on the street, they say. And while cops may receive a call about an overheard disturbance, the vague report to 911 is usually not enough to pinpoint the correct apartment or hotel room. There are few things more dispiriting, they say, than hearing of a woman's cries for help and being unable to find her.

5. Closing Craigslist's "adult services" section will significantly affect the sex trade.



Although Craigslist offered customers an important means to connect with sellers of sexual services, its significance has probably been exaggerated.

Even before the site's "adult services" section was shut down, it was falling out of favor among many users. Adolescent pranksters were placing ads as hoaxes. And because sex workers knew that cops were spending a lot of time responding to ads, they were increasingly hesitant to answer solicitations. I found that 80 percent of the men who contacted women via Craigslist in New York never consummated their exchange with a meeting.

How the sex trade will evolve from here is anyone's guess, but the Internet is vast, and already we are seeing increasing numbers of sex workers use Twitter and Facebook to advertise their services. Apparently, the desire to reveal is sometimes greater than the desire to conceal.

su185@columbia.edu

Sudhir Venkatesh is a professor of sociology at Columbia University and the author of "Gang Leader for a Day: A Rogue Sociologist Takes to the Streets."

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