This study examined one-year rehospitalization rates for patients who were discharged from Austin State Hospital between August 1, 1997, and July 31, 1998, while taking olanzapine, risperidone, or a conventional antipsychotic. Time to readmission was measured by the product-limit formula. Although conventional antipsychotics were associated with a lower rehospitalization rate, no significant difference in the one-year rehospitalization rate was observed between the groups. At 180 days after initial discharge, the patients who received olanzapine had a higher rate of rehospitalization than patients who were taking conventional antipsychotics. Conventional antipsychotics were associated with a lower one-year rehospitalization rate than risperidone or olanzapine.