You require a permit as an Operator of a prostitution establishment. There are various Information portals on the Internet, or get some information at the Trier Public Order Office (Ordnungsamt), tel. +49 (0) 651/718-1323.

Building law
Prostitution in a dwelling: Sex workers who live in their own home (registered as their main residence or a regular dwelling place) may work there alone. In this case, you will not need to have a usage permit under building law.

Rent-by-the-hour apartments/brothels/clubs: If you would like to hire rooms for work together with others, you will need to have a usage permit from the Bauaufsichtsbehörde (‘building control authority’). Sex work in dwellings or operations similar to brothels is only permitted in commercial, industrial and mixed areas. However, there are four prohibited areas. The Bauaufsichtsbehörde (‘building control authority’) will be able to tell you exactly where you can work. It is best to obtain advice from the Amt für Bauen und Wohnen (‘Department of Building and Housing‘).

Commercial law
There is no commercial registration of sex workers. However, operators must register with the Ordnungsamt (‘Department of Public Order‘), otherwise they can be punished. The Ordnungsamt (‘Department of Public Order‘) will inform the Finanzamt (‘tax office‘).

Condom requirement in accordance with the German Protection of Prostitutes Act (ProstSchG)
As the operator of a club, brothel, a love apartment or another prostitution establishment you must draw people’s attention to the Condom Requirement. This is set out in the Protection of Prostitutes Act. To this end you must for instance hang up a sign which everyone can see.