This paper describes the derivation of a 22-item Situational Confidence Questionnaire for heroin users [SCQ (Heroin)]. Results revealed the SCQ (Heroin) to be an internally consistent scale with an acceptable level of test-retest reliability. Construct and discriminant validation were demonstrated through moderately significant correlations of all subscales with the short form of the Beck Depression Inventory. Factor analysis revealed a three-factor structure which could be labeled: coping with or enhancing arousal states, casual or occasional usage, and coping with negative emotions.