Sex-based differences in multiple sclerosis (MS) are evident in various aspects of the disease, including biological processes, clinical presentation, MRI findings, and disease outcomes. The emerging field of precision medicine offers a promising approach to addressing the complexity of MS. By leveraging genetic markers, biomarkers, and other biological factors, precision medicine aims to tailor treatments to individual patients. However, the potential impact of sex and gender on treatment outcomes remains largely unexplored. Here, we examine how the two sexes/genders differ in MS, what evidence supports these differences, and how we can capture and utilize these differences to improve disease management. Additionally, we discuss the importance of promoting personalized medicine by incorporating gender medicine into comprehensive healthcare strategies.