AbstractOne of the fundamental challenges of modern neuroscience is to understand how memories are acquired, stored, and retrieved by the brain. In the broadest terms, attempts to dissect memory can be broken down into four experimental disciplines: (1) identification of molecular components, (2) ex vivo and in vivo cellular analysis of neuronal function, (3) theoretical modeling approaches of neural systems, and (4) organismal‐level behavioral analyses. Our objective here is to offer a conceptually unifying perspective and to discuss this perspective in relation to an experiment analysis of memory in Drosophila. © 2003 Wiley Periodicals, Inc. J Neurobiol 54: 238–253, 2003