It's a source of national pride in Brazil - to be named Miss Bumbum.
And hundreds of women from across the country apply - but only 27 are chosen to compete for best butt.
While the world's best athletes compete in the Olympic games in Rio, the Miss Bumbum contestants stopped traffic in Sao Paulo.
One contestant said if Miss Bumbum were an Olympic event, Brazil would always win gold.
"Definitely, Brazil would win lots of gold medals. Every year since the Olympics began, we would win gold because Brazil is known for the prettiest bums in the world," Erika Canela, Miss Bumbum contestant, said.
Just 15 women will compete in the final in November.
And as they look forward to the competition, others will simply take in the view from behind.