Substance use disorders are among the most frequent psychiatric disorders found in suicides. In psychological autopsy studies between 19% & 63% of all suicides suffered from substance use disorders, mostly from alcohol use disorders. Suicide risk is highly increased in substance use disorders, particularly in alcohol use disorders, & in co-morbid alcoholism & depression. So far, some risk factors for suicide have been identified in alcoholism. Nevertheless, various questions about the relationship between substance use disorders & suicide remain open, which indicate directions for future research. (101 refs.)