The Global Neurodegeneration Proteomics Consortium (GNPC) released one of the largest dementia-related proteomic datasets, including 250 million protein measures from over 35,000 biofluid samples linked to Alzheimer’s, Parkinson’s, and other neurodegenerative diseases. Analyses revealed disease-specific and shared protein signatures, identifying biomarker candidates and molecular pathways. This open-access resource is expected to accelerate diagnostics development and therapeutic strategies targeting neurodegeneration worldwide.