Previous studies using probability samples have found a noticeable, but small association between violence and psychiatric disorder. In this article, we analyze data from the National Comorbidity Survey (NCS) to further examine this question. Psychiatric diagnosis of survey responses was based on a modified version of the Composite International Diagnostic Interview. The NCS study also included items that permitted self-report of violent behaviors in the past year. People with 12-month diagnoses of anxiety disorders, dysthymia and major depression were three to four times more likely to admit violent behaviors than those with no disorders. People with bipolar disorder or drug and alcohol abuse were eight times more likely to report violent behaviors. People with co-occurring non-substance and substance abuse disorders were more likely to report violence than those with only non-abuse disorders. Adjusting violence rates by population base rates shows demographics including ethnicity and gender to be a better predictor of violent behavior than psychiatric diagnosis. The NCS findings approximate those in other probability studies and echo the conclusions of the 1996 Consensus Statement by Advocates and Researchers on violence and mental illness; namely, mental illness is only a weak predictor of violent behavior.