Tonight, Diane Sawyer takes an intimate look at the business of prostitution, from the most expensive New York penthouses to the streets of Reno, Nev.

At left, Sawyer visits the Moonlight Bunny Ranch, a legal brothel in Carson City, Nev. About 800 women work legally as prostitutes in Nevada, but there are many more who work against the law. There are an estimated 10,000 illegal prostitutes in Las Vegas.
(ABC)