Dopaminergic hyperactivity mediated via D2 receptors is implicated in the etiology of positive symptoms of schizophrenia, but selective D2 antagonists provide imperfect therapy. This article describes a subanalysis of a trial of risperidone, a combined 5-HT2A/D2 antagonist, in 513 patients with DSM-III-R chronic schizophrenia. Risperidone at 2, 6, 10, and 16 mg/day was compared with placebo and haloperidol 20 mg/day. All doses of risperidone and the 20-mg dose of haloperidol were superior to placebo (mean change from baseline on the PANSS positive and general psychopathology subscales). The 6-mg dose of risperidone also produced significantly more improvement than haloperidol 20 mg. We conclude that risperidone is an effective drug for patients with positive features of schizophrenia.