Mostly I take photographs in times of research. Whores' Glory was shot in 30 days, 10 days for each segment, but the research for each part lasted a couple of months.

If you're a prostitute, this is your day: You party, you have customers until four or six in the morning, then you sleep. You wake at noon, watch soaps on TV, take two or three hours to fancy up yourself, and then you start waiting for customers. That's your life. And some days no customers come. There's no party. There's nothing. You sit there and wait. If you're educated you can read books, but in Bangladesh and most other places you watch TV or listen to music or cook.

Sometimes the presence of a camera is like opening a door, because many people want what Andy Warhol called "15 minutes of fame." But prostitutes don't want that.

I don't aestheticize anything. I don't even use lights. The working girls do one thing all day: They make themselves pretty. That's their job and their money. In a way, I had the best makeup artists, hairdressers, and art designers in the world.

Prostitution will always exist in every society, so I believe in a fair trade. Open the doors for women to earn their money without having pimps. The worst thing is to criminalize it, because then you open the doors for pimps, criminals, and trading.

Whenever a man enters the realm of prostitutes he's always regarded as a possible customer. If you enter as a woman, you're regarded as somebody who could be in the same place. Being a man brings the perspective of flirtation.

La Zona is such a closed area, a dangerous, outlaw area. My time in the Zona was a time outside of society, almost out of the real world. And the girls there had such a sense of irony and sarcasm. They were also really interested in my film. They'd be like, "Thank God we live in Mexico, because our kind of prostitution has a heart. We wouldn't want to sit behind a glass cage or be sold by our own mothers. We have free will."