Cognitive impairment has been associated with higher risk of alcoholism and relapse. Recent theoretical refinements have separated inhibition of dominant response and inhibition of proactive interference. We assessed the latter using a directed-forgetting procedure in 38 recently detoxified individuals with alcoholism and in 26 controls. On this task, memory performance of letter trigrams was compared when presented alone, followed by a second trigram to be recalled, then a second trigram to be forgotten (directed-forgetting condition). Individuals with alcoholism recalled more letters to be forgotten and performed worse than controls in the directed-forgetting condition, which significantly correlated with the duration of alcoholism.