It's nothing new of course. The trend was well under way in Victorian London over 130 years ago, when the upper class wanted to see for themselves the poverty in the East End. It took off again when Nelson Mandela was freed from jail in South Africa and tourists flocked to the townships and places linked to apartheid.
Now it's big business in cities like Mumbai, Rio de Janeiro, Beijing and even New York City, home of the Tenement Museum.
There's a similar trend in Belfast. Not so much slum tourism as conflict tourism. More and more tourists are curious about the areas that suffered heavily during the Troubles, as well as all the paramilitary murals and peace walls.
But opinions are divided over whether this fashion is good or bad. Those in favour say that as well as bringing money into desperately poor areas, it opens the eyes of people who may have lived in comfortable conditions all their lives and know nothing of serious hardship except what they see on TV.
Those against point out that a lot of the money raised doesn't go to the locals at all but to outsiders who've never set foot in the areas visited. And people's eyes may be opened for a few days but when they return to their normal privileged lives they soon forget what they've seen.
At its worst it's a voyeuristic search for cheap thrills and titillating squalor, taking away the dignity and privacy of those they're gawping at and not leaving them with any long-term benefit.
I'm of two minds about it all myself. Yes, there's little financial gain for the places the tourists visit, and little change to the prevailing poverty and degradation. But then again, I think many of those tourists are quite sincere in wanting to know about the wretched lives some people have to endure, and they return home genuinely enlightened and humbled.
The more people experience the grim reality of those forced to exist on the crumbs falling from the millionaires' well-stuffed mouths, the better.
My thanks to James Melik of the BBC for his article on the subject
