For years, plastic surgeons thought the proportions of a beautiful buttocks should follow the Fibonacci sequence. Now, people are looking for a more Kardashian shape. In the history of gluteal enhancement, Mexico City stands out. It was here, in 1979, that a plastic surgeon, Mario González-Ulloa, first installed a pair of silicone implants designed specifically for the buttocks. The textbook calls González-Ulloa the "grandfather of buttock augmentation." The early 2000s saw a new generation of Mexico City buttock transformation luminaries, notably Ramón Cuenca-Guerra. Cuenca-Guerra laid out four characteristics that "determine attractive buttocks" as well as the five types of "defects," with strategies for correcting each one. I, for instance, have defect type 5, the "senile buttock." While I understand the value of standardizing procedures and setting guidelines for surgical practice, I tripped over Cuenca-Guerra's methodology. How and by whom had the determinants been determined?