The biomarker field is advancing quickly, and aside from mass biomarker arrays analyzed by AI, single biomarkers have been established to help in predicting disease course and monitoring response to therapy. The role of NfL is by far the most advanced in aligning with inflammation, but GFAP is gaining recognition as a possible indicator of disease progression. Whether such biomarkers also play a role in pediatric onset disease or inform on conditions such as MOGAD and NMO will also be explored. Level of Information: AdvancedThe biomarker field is advancing quickly, and aside from mass biomarker arrays analyzed by AI, single biomarkers have been established to help in predicting disease course and monitoring response to therapy. The role of NfL is by far the most advanced in aligning with inflammation, but GFAP is gaining recognition as a possible indicator of disease progression. Whether such biomarkers also play a role in pediatric onset disease or inform on conditions such as MOGAD and NMO will also be explored. Level of Information: Advanced