Perky ones, fat ones, hairy ones. Even tattooed ones. For every person, there is a bottom. And at the Recoleta Cultural Centre in Buenos Aires, they've all been on show, in all their glory.
The proud purveyor of all these posteriors is Chilean visual artist Catalina Riutort. She says the exhibition is one of "common, everyday people, represented by barcodes, which correspond to their identity card".
Some 600 bottoms on show
She adds that it also talks about hidden identity.
"It's the people we never see. Because we're all used to seeing what the media show us. Standardised people, models, perfection, happiness. There's also a bit of irony about identity, because in this accumulation of people, you can't recognise anyone."
Not even Ms Riutort herself, who confessed that her fine behind is among the 600 bottoms on show (though she wouldn't say which one). Most of them are Chilean, though a couple of Argentine and American posteriors are also included.
Is it art?
The "Carne de Identidad" (a play on the Spanish words for "identity card" - "carnet de identidad" and "flesh of identity" - "carne de identidad") exhibition has been drawing in the crowds in Buenos Aires. Its next stop is Chile and then, if the civil unrest there dies down, Bolivia.
Is it art? Alfredo Cernadas, an art critic for the Buenos Aires Herald, certainly seems to think so. He was quite taken by the bottoms, which he said were "beautifully photographed".
So I asked him if he thought bottoms had more artistic potential, say, than other parts of the human body.
"Not necessarily," he says. "It all depends on who photographs them, or draws them, because a foot may be just as interesting. Or a hand. Or eyes, well you name it. Or even ears."
But fans of Kylie Minogue would beg to differ. Now well into her 30s, the Australian songstress is the proud owner of what is arguably the world's most famous and most sought-after bottom.
Actress and singer Jennifer Lopez, meanwhile, has gone on record as saying that her behind is even more famous than she is, reportedly insuring it for $200,000.
Many Argentines are also proud of their behinds.
"I haven't got a problem with mine," said one greying lady outside the exhibition. "My bottom says I'm sexy," said a nearby shopkeeper, as he wiggled it obligingly.
Kylie Minogue: Owner of arguably the world's most famous behind
"Each country has a special taste regarding its women," says Dr Jose Juri, Argentina's plastic surgeon to the stars.
"For example, in the United States, the most important thing is good breasts. In our country, for Argentine people, we prefer a good buttock."
Surrounded by awards and photographs of ageing Latin American chat-show hostesses and actresses, Mr Juri was only too happy to explain the mystique behind the behind.
"The buttocks have some kind of special attraction for men. Not for every man. But for most men, and women know this perfectly well."
Argentines like to see themselves as being among the world's most beautiful people. Yet that doesn't stop them heading in their thousands each year to plastic surgery clinics, for that all important nip and tuck.
And for those who lack the liquid assets, or feel plastic surgery is a little extreme?
Well, there is some solace. For no matter how bad they might feel about their rear view, beauty is in the eye of the beholder and even here in Argentina that still counts.
And if that doesn't work, you can always pop along to the exhibition and feel comforted in the knowledge that no matter how bad your behind looks, there's always someone's which is far, far worse.