Background: Studies performed with schizophrenic adults who were resistant to classical neuroleptics showed improvement in 30% of the patients when treated with clozapine. Very early onset schizophrenic patients benefit only partially from conventional antipsychotics and are at increased risk of developing extrapyramidal symptoms; clozapine may offer an alternative treatment for these patients. Method: Eleven neuroleptic-resistant children (< 13 years) with schizophrenia were treated with clozapine. Improvement was monitored during the first 16 weeks using the Brief Psychiatric Rating Scale, Positive and Negative Syndrome Scale and Clinical Global Impression. The mean clozapine dosage was 227.3 (s.d. 34.4) mg/day at the end of the 16 weeks. Results: There was art overall statistically significant reduction in all parameters, especially positive symptoms, implying a favourable outcome. Most of the improvement occurred during the first 6 to 8 weeks. The major side- effects were somnolence and drooling (no agranulocytosis). Conclusion: Clozapine may be a promising drug for the treatment of resistant childhood- onset schizophrenia.