So you think Alzheimer’s is a neuronal disease? Well, yes, but you might as well think again. Even as the amyloid hypothesis is growing stronger with human genetics and longitudinal biomarker studies, decades of neurocentric research have given way to a broader appreciation that Aβ and tau intersect with the glial and vascular system and are subject to new forms of genetic regulation in the aging brain. What’s more, parabiosis shows that the blood itself carries signals into the brain that can powerfully influence its aging and degeneration. These topics dominated the first Zilkha Symposium on Alzheimer’s Disease and Related Disorders, hosted on April 4 by the University of Southern California. Gabrielle Strobel’s series covers the meeting highlights.