There are in fact numerous arguments both for and against the legalization of prostitution.
Those opposed to it point out that it can lower the moral standards of any community it takes place in. Some evidence suggests that areas with legal prostitution even face some social disorder, as fewer men get married and those that do are more prone to cheating. Even when legal, many prostitutes are forced into the trade for economic reasons and sometimes even by human traffickers.
Supporters of legalized prostitution advocate that it removes the stigma of the profession. When in broad daylight, sex workers themselves are able to be better protected and given needed services and programs. The sex tends to be safer for everyone involved too. They also point out that consenting adults not hurting anyone else should be allowed to do as they please.