We thank Drs. Robertson and Wilson for their interesting comments on our report of the efficacy and tolerability of four novel compounds in the treatment of schizophrenia. The report by Berk and colleagues (4) of the ability of mirtazapine differs in two important aspects from our report of the ability of SR46349B, which diminish its relevance for our article; we can cite only the most highly relevant literature here. First, mirtazapine has a much more complicated pharmacology than SR46349B, which is a highly selective 5-HT2A/2C antagonist, e.g., mirtazapine is also a potent α2-adrenoceptor antagonist, so that it is not possible to attribute any benefit it may have in schizophrenia solely to its effect on 5-HT2A/2C receptors, as is the case with SR46349B. More important, the study of Berk and colleagues was an augmentation study: mirtazapine was added to haloperidol, whereas SR46349B was given as monotherapy to acutely psychotic patients. There is no evidence that we are aware of that mirtazapine is effective as monotherapy for patients with schizophrenia. We did cite evidence that M100907, a highly specific 5-HT2A antagonist, is useful, to some extent at least, in treating schizophrenia.