There is considerable heterogeneity in the psychopathology of schizophrenia and the response to neuroleptic treatment, at least some of which may result from ethnicity and gender differences among subjects. We review the literature relevant to ethnic and gender differences in psychopathology and neuroleptic response in schizophrenia. Studies reveal several diagnosis- and treatment-related differences in schizophrenia among different ethnic and gender groups. Some of these differences might be biological in origin, others due to cultural or environmental factors. In studies conducted in our center, we found no differences in psychopathology or amount of neuroleptic therapy between African-American and Caucasian patients. We did note that African-American patients in our sample had a somewhat greater risk of developing tardive dyskinesia than their Caucasian counterparts. The incidence of tardive dyskinesia was similar for males and females. Our studies of neuroleptic-induced tardive dyskinesia were restricted to patients over age 45, though there were no ethnic or gender differences in the daily neuroleptic dose. Future work in this area should carefully compare ethnic and gender differences in treatment response.