Statistics from the Department of Justice in Ireland show that Limerick is overtaking Dublin in its number of brothels.
Prostitution is also increasing in counties such as Wexford, Monaghan, Roscommon and Longford.
Gardai are cracking down on prostitution and have shut down 28 brothels this year already. Brothels were discovered in 14 different counties in the first half of this year, compared to six counties for the entire 2009 year.
Geraldine Rowley, from Ruhama, an organization that works for women affected by prostitution, said new legislation is needed.
"The last piece of legislation brought in to govern the sex industry came in 1993, when there were no mobile phones and very few people had access to the internet,” Rowley told The Herald.
"In these times the pimp would have to be on site, whereas now he can use the internet and mobile phone to co-ordinate his sordid business, “ she said.
Now, she says, criminal gangs can set up a new brothel only hours after being shut down.
"There is no deterrent to criminals operating in the sex industry, it's extremely lucrative," Rowley said. "Their customers can just contact them on their mobile phones and move to a new location."