On Berlin's Kurfurstenstrasse, they are out in force - women in their late teens to late 40s, some of them perhaps older but dressed to look younger. Many are wearing puffer jackets and tight-fitting jeans under their miniskirts.
A shiny grey BMW stops and the driver winds down its window. One of the women steps up on the passenger side. There's a brief exchange of words - five or six syllables, not more - and the car is driven off again. A few minutes later the same woman walks towards the LSD (Love, Sex & Dreams) adult entertainment store on the corner with Potsdamer Strasse, a client in tow. A girl on her way home from school skips down the road in the other direction.
Scenes like this can probably be seen in most large cities around the world. What is unusual about Germany is that prostitution there has been legal since the Social Democrat (SPD)-Green coalition Government changed the law in 2002.
The aim of that change was, as SPD politician Anni Brandt-Elsweiler put it at the time, "to improve the situation of prostitutes by giving more power back into their own hands, by strengthening their self-confidence and their legal position when dealing with clients and pimps".
In Berlin, political support for the law change remains strong. This year, SPD and Green city councillors compiled a little booklet that they distributed among Kurfurstenstrasse residents, pleading for tolerance and understanding for the sex trade in their midst.
"City life and prostitution have gone hand in hand for more than 100 years," it said. "Prostitution is notillegal."
But across the border in France, politicians are contemplating a ban on paying for sex, and German public opinion appears to be changing as well.
Last month, veteran feminist Alice Schwarzer published a book entitled Prostitution: A German Scandal. Emma, the feminist magazine Schwarzer started in 1977, has also published a petition against the law, signed by 90 celebrities from the right and left of the political spectrum.
They say Germany's experiment with liberalising prostitution has failed spectacularly, turning the country into "the bordello of Europe", with increasing numbers of brothels opening near the border.
The 2002 law was trying to make sex work a job like any other. But only 44 sex workers in Germany are registered with the national insurance scheme. Social workers say most prostitutes cannot afford to put aside money for a health insurance policy.
Schwarzer and her supporters have championed the legal situation in Sweden, where it is illegal to buy sexual services but not to sell them.
She likens German attitudes to prostitution to those towards paedophilia in the 1970s - a wilful blindness towards an injustice.
"Prostitution, like paedophilia, is characterised not by equality, but drastic power imbalances," she recently wrote in Die Zeit.
Schwarzer is not without her critics. At the launch of her book last week, she was harangued by a group of pro-prostitution campaigners.
Alexa Muller, 38, is one of the sex workers who passionately defends Germany's path on prostitution law.
"Women can run brothels responsibly here and not be prosecuted, that's an incredible achievement," she said.
"And sex workers are autonomous legal agents. They can take a client to court if he refuses to pay up."
She accused Schwarzer of spreading ignorance and using misleading figures.
Criminalising clients, as it is done in Sweden, she said, would only cement sex workers' victim status.
"We are not victims, we are adventurous sex goddesses," she said.
If only 44 sex workers are registered for the public health scheme, she claimed, it was because 10 years of the new law haven't been enough to remove social stigma.
Most sex workers have more than one job, and even if they work full-time, they are more likely to register as a "performance artist".
Muller started having sex for money to fund her degree in design, and went full-time seven years ago.
"To be frank with you, I found it more creative, fun and fulfilling work than being a graphic designer."