This study considered the role of schema-level cognitive processes in alcohol and opiate abuse. It examined the hypothesis that alcohol abuse will be associated with the use of “blocking” behaviours to reduce the experience of emotions (secondary avoidance of affect), while opiate abuse will be associated with a tendency to avoid emotions being activated in the first place (primary avoidance of affect). The sample consisted of 30 patients who abused alcohol, and 30 who abused opiates. Each completed the Young Compensatory Inventory (YCI) and the Young-Rygh Avoidance Inventory (YRAI). There were no differences between the groups in their absolute levels of schema processes (YCI and YRAI scores). However, they differed in the way in which the severity of use was associated with the level of YRAI behavioural-somatic avoidance. Among alcohol abusers only, severity of use was greater in those who were more likely to avoid affective arousal in this way. This association with severity was not found among opiate abusers. Implications are discussed for existing treatments and for the use of schema-level cognitive behavioural interventions with substance-using populations.