Brothel owners are trying to keep up with demand, opening multi-storey, "mega-brothels" across the country, such as "Paradise" on the outskirts of Stuttgart.
“Prostitution has always been a social need. It wasn’t invented by anybody,” marketing manager Michael Beretin told Amos Roberts from SBS's Dateline program.
Inside the brothel, men must wear bathrobes, but can mingle with the naked girls in luxury surroundings, before making their choice.
"The women are free, they can do what they want," Mr Beretin said. "If they want to, they only go to a room with a guy. If they'd rather drink champagne and talk, they do that."
Germany relaxed its prostitution laws 12 years ago, and brothel chains like Paradise are now attracting customers from across Germany and sex tourists from far beyond.
"You can take at five o'clock a blonde one and at nine o’clock a black one,” customer Peter told Amos. “It’s not getting boring."
The 2002 Prostitution Act was designed to improve working conditions for prostitutes and make it possible for them to get health insurance and social security.
But while brothels like Paradise say they follow best practice and require appropriate paperwork from all the women, it’s unclear how many are being forced into prostitution elsewhere.
The government believes many prostitutes are being exploited, and already has plans to change the law.
"At the time it was thought that legalising prostitution would improve the prostitutes' situation," said Christian Democratic Union MP, Sylvia Pantel. "But that totally failed."
"Germany doesn't want to be the brothel of the world," she said. "Nor do we want to create incentives to attract sex tourism to Germany."
One of those who says she was failed is "Maria". She escaped abuse in Romania, but ended up working as a prostitute in Germany for four years.
"I never forget all the number of men, I didn’t forget from the first day, it was disgusting," she said, on agreement of anonymity.
"In the most situations the woman is not alone… she has a boyfriend… we call it 'pimp'," she says.
Concerns about exploitation and trafficking have led to much stricter laws in some European countries, and Germany is looking at introducing its tighter regulations later this year.
They could include a brothel licensing system, raising the minimum age of prostitutes to 21 and granting residency to trafficking victims who cooperate with police.
But Sylvia Pantel said the government didn't want to try and ban it altogether.
“We believe that if it takes place in a regulated environment, women are not exposed to violence or forced to prostitute themselves, so we don’t want to prohibit it,” she said.
For an industry worth $21 billion a year in Germany, it remains to be seen what impact any change in the law will have.
