Prostitution
There are some places, where prostitution is legal, but advertising for it is not. In Germany since 2016 both is legal. Since the new prostitution law (Prostituiertenschutzgesetz vom 21. Oktober 2016 (BGBl. I S. 2372)) was included, advertising is not prohibited anymore as long as youth protection is respected.  Potential customers find all necessary information about the prostitutes they need in the web, and are able to contact them with their phones. Usually customers visit the apartment of the prostitutes or order them to their home or hotel room. In the Netherlands, both prostitution and advertising for it are legal as well. Hidden advertising is still done. It can take different forms: