Long-lasting forms of learning-related synaptic plasticity require transcription and yet occur in a synapse-specific manner, indicating that there are mechanisms to target the products of gene expression to some but not other synapses of a given cell. Studies in a variety of systems have indicated that mRNA localization and synaptically regulated local protein synthesis constitute one such mechanism. The cellular and molecular mechanisms underlying RNA localization and regulated translation in neurons are just beginning to be delineated, and appear to be similar to those used in asymmetric non-neuronal cells.