Although genes associated with human autism spectrum disorders have been identified, bridging the gap between genetics and the patchwork of behavioral deficits associated with the disease remains an enormous challenge. Peñagarikano et al. (2011) now show that mice lacking CNTNAP2, a gene that causes a rare form of epilepsy associated with autistic features and language impairment, display similar phenotypes to their human counterparts, raising hopes that such models may speed the identification of neuronal circuitries underlying the core features of autism.