The aim of the study was to examine the relationship between neuropsychological impairment in severe alcohol dependence and relapse. This was assessed following inpatient detoxification over a period of three months. Participants were tested on measures of neuropsychological functioning at the end of a seven to ten day stay in an inpatient alcohol detoxification unit. Participants were followed up three months later by telephone to ascertain the number of days in which alcohol was consumed during this period using the Timeline Follow Back procedure (TLFB). A correlation and regression design was used to analyse results. An inpatient alcohol detoxification unit. Thirty-four residents in an inpatient alcohol detoxification unit. Executive dysfunction during detoxification was found to predict number of days drinking in the three months following discharge. Neuropsychological impairment, and specifically executive dysfunction, appears to be a significant barrier to ability to remain abstinent from alcohol following a period of detoxification. Given the high rates of relapse found within the current study it suggests that the cognitive domains that executive functioning describe are particularly relevant in facilitating abstinence in alcohol dependence.