Abstract: Eighty alcohol and/or drug dependent women who were consecutive admissions to an outpatient alcohol and drug service were interviewed with the aim of gathering information regarding childhood adversity, psychiatric comorbidity and alcohol and drug history, including extent of treatment and alcohol and drug related criminality. A secondary aim of the study was to investigate associations between both the multiplicity of alcohol and drug dependence diagnosis and the presence of psychiatric comorbidity in relation to exposure to childhood adversity, including sexual, physical and emotional abuse.The data demonstrate that the study sample was a relatively severe group of alcohol and drug dependent women. A sizeable percentage came from backgrounds characterised by parental separation, conflict and alcohol and drug problems. Many were regularly exposed to physical abuse perpetrated by both parents or main parental figures and over two-thirds were exposed to some form of sexual abuse within their first 15 years. Sixty percent had been dependent on more than one psychoactive substance, with half having undergone previous alcohol and drug treatment. The women also presented with substantial histories of criminal convictions, with a quarter having served a prison sentence. The results indicate the presence of extensive psychiatric comorbidity in the sample. Two-thirds of the women met current DSM-IV criteria forat least one of the following Axis I disorders: major depressive syndrome, social phobia or bulimia nervosa, while nearly half had antisocial personality disorder. More importantly, significant associations were found regarding the presence of psychiatric comorbidity in relation to four measures of severe childhood adversity, i.e. childhood sexual, physical and emotional abuse and parental problems. Multiplicity of alcohol and drug dependence diagnosis was associated with severe emotional abuse, severe parental problems andpsychiatric comorbidity. Emotional abuse during childhood was the most pervasive indicator of comorbidity and multiplicity of alcohol and/or drug dependence. The main implication for clinical practice arising from the results of this study is the need for the development of a broader approach to alcohol and drug service provision. In order to achieve positive treatment outcomes, alcohol and drug service may need to routinely screen and plan treatment for unresolved childhood trauma, psychiatric disorder and other problems related to alcohol and drug use in all clients presenting for alcohol and drug treatment