The aim of this paper is to report the prevalence of 12-month comorbidity between DSM-IV alcohol use disorders (abuse or dependence) and anxiety, affective and drug use disorders in the adult Australian general population and to examine the disability and health service utilisation associated with this comorbidity. The study uses data from the National Survey of Mental Health and Well Being (NSMH&WB). The NSMH&WB is a cross-sectional survey of 10,641 Australian adults conducted in 1997 that measured the prevalence of DSM-IV mental disorders in the previous 12 months and associated disability and health service utilisation. Results show approximately one-third of respondents with an alcohol use disorder (abuse or dependence) met criteria for at least one comorbid mental disorder in the previous 12 months. They were 10 times more likely to have a drug use disorder, four times more likely to have an affective disorder and three times more likely to have an anxiety disorder. Respondents with an alcohol use disorder and a comorbid mental disorder were significantly more disabled and higher users of health services than respondents with an alcohol disorder and no comorbid mental disorders. These results reinforce the need for both mental health and drug and alcohol professionals to be provided with education to assist with appropriate identification, management and referral of clients presenting with this complex range of disorders.