Marc Suárez-Calvet, MD, PhD, Barcelonaβeta Brain Research Center (BBRC), Barcelona, Spain, shares insights on the molecular processing and secretion of brain phosphorylated-tau (p-tau). Interestingly, levels of some p-tau species in fluids, either cerebrospinal fluid or blood, increase earlier than tau PET and therefore, may reflect amyloid pathology better than the tau pathology. It is possible that a proportion of the p-tau is released as an active secretion in response to the amyloid pathology. Future research may need to reconsider where we classify p-tau biomarkers in the ATN classification. This interview took place at the Alzheimer’s Association International Conference (AAIC) 2022 in San Diego, CA.