A biochemical hypothesis - that Alzheimer’s disease (AD) is a progressive cerebral amyloidosis caused by the aggregation of the amyloid b-protein (Ab) - preceded and enabled the discovery of etiologies. This volume serves as a record focused on bringing together investigators at the forefront of elucidating the structure and function of hippocampal synapses with investigators focused on understanding how early assemblies of Ab may compromise some of these synapses.