How genes and environment interface to generate major psychiatric disorders such as schizophrenia has been puzzling, as are the relative roles of neurons and glia in such disturbances. Tomonaga and colleagues have recently reported striking neurobehavioral abnormalities in mice expressing Borna disease virus phosphoprotein (BDV-P) selectively in glial cells. The study provides a novel approach of linking environmental and genetic factors to behavior by producing genetically engineered mice. The key role for glial BDV-P implicates neuron-glia interactions in the pathogenesis of psychiatric conditions.