Epigenetics is an environmentally-induced persistent alteration in gene expression that has only recently been shown to play a powerful role in brain function. Epigenetic alterations of DNA may be pharmacologically modifiable and also offer novel interventions for brain disorders. This session will provide an overview of epigenetic processes and how they can be monitored in the brain. The role of epigenetic alterations in gene expression and the phenotypic manifestations of autism, schizophrenia, post-traumatic stress disorder and Huntington’s disease will be reviewed, as well as the implications for novel pharmacologic treatments.