Dr. Saint-Hilaire is an Associate Research Physicist at the Space Sciences Laboratory (SSL) of the University of California in Berkeley. Since his arrival in Berkeley in 2005, he has been part of the NASA Ramaty High Energy Solar Spectroscopic Imager (RHESSI) science and operations team. The bulk of his observational work has concentrated on X-ray data analysis from solar flares, and solar radio observations from low frequencies to microwave, with a few excursions in other fields (sungrazer comets, polarized visible light from flare loops, and extra-galactic radiobursts). Space instrumentation and mission design in radio and X-rays are his current focus.

Dr. Saint-Hilaire is the PI of the NASA GRIPS (Gamma-Ray Imager/Polarimeter for Solar flares) high altitude balloon payload.