Autistic disorder belongs to a broad spectrum of pervasive developmental disorders. Autism is a clinically and genetically heterogeneous condition. It is characterized by impairment in a broad range of social interactions, communication, and repetitive patterns of behavior and interest. Although the exact etiology of the condition is not known, family and twin studies strongly support genetic factors in autism. Genome-wide scans suggest several susceptibility loci that may contain one or more predisposing genes. However, no such genes have been identified so far that predispose patients to autism. The condition is over 90% heritable, but the mode of inheritance is not clear. Moreover, it does not seem to be a single gene disorder. There is no cure for autism. Individualized structured education, family support services, and antipsychotic drugs are recommended. These may alleviate some behavioral problems. The identification of autism genes, an understanding of the neurobiology of the condition, and additional clinical studies may help to develop pharmacological interventions in the future.