It is our long-term goal to understand at a molecular and functional level how neurons form synapses with each other. Our current research aims to delineate the pathways that induce and coordinate synapse formation in brain development. In addition, we investigate how synapse-organizing mechanisms contribute in the adult nervous system to the activity-dependent remodeling of neuronal connectivity and networks. Attaining these goals is of importance to human health as altered synapse formation and stability underlie devastating brain disorders, including those that are neurodevelopmental, neurological, and related to addictive drugs. We pursue our goals by integrating biochemical, proteomic, cell biological, physiological, and behavioral experiments, spanning the range from molecules to genetically modified mice.