It was clear from the start that multitalented Ilionis Guillaume—born in Croix-des-Bouquets, Haiti on 13 January 1998—was a gifted athlete. She burst onto the national stage in 2015 at France’s scholastic championships in Clermont-Ferrand, setting French records in the 60 metres hurdles and high jump, with a leap of 1.82 m. Just two weeks later, at the French under-20 championships in Nantes, she proved it was no fluke, winning the 60 metres hurdles, high jump and triple jump. 

That same year, Ilionis finished 4^th in both 100 metres hurdles and triple jump at the World Athletics U20 Championships. In late 2016, she relocated from Montpellier to France’s Var region to train with Laurence Bily and world triple jump champion Teddy Tamgho. Her breakthrough came in July 2017, when a 13.97 m triple jump at the U20 Championships clinched her first European medal. Alongside her sporting success, Ilionis completed a Baccalauréat in Management Science and Technology and began a two-year degree in customer relations in 2018. That February, she was crowned French indoor champion in the triple jump with a personal best of 14.07 m.

As part of Stade Sottevillais 76, a Rouen-based athletics club, Ilionis took her performances to new heights in 2024. She won bronze at the European Championships in Rome with a 14.43 m jump—her first medal at the elite level. Just 10 days later, she set a new personal best of 14.59 m in Guadalajara. And with it, a chance to represent France at the Paris 2024 Olympic Games, where she reached the finals and placed 12^th overall.

Looking to balance her athletic pursuits with a career move, Ilionis Guillaume joined the SNCF Athletes programme on 16 June 2025. Thanks to the flexibility she’ll have as a Customer Service Assistant Manager on the RER D Line, she’s already setting her sights on her next big goal: standing on the podium at the Los Angeles 2028 Olympic Games.