A directive from Wilhelm Frick, Reich Minister of Interior, creates a network of official brothels throughout German territory. Women who try to work as prostitutes on their own are imprisoned in concentration camps for "antisocial behavior."
In the east, the brothels are primarily made up of women who are forced into prostitution, many kidnapped off the streets. It's estimated that over 34,000 women are forced by the Nazis into sexual slavery this way.
In France, however, the Nazis simply take over the network of brothels that was already controlled by the French government. All other prostitution is banned and those prostitutes in the "official" brothels are paid their usual rates.