The purpose of the protocol is to evaluate the efficacy of olanzapine compared with Aripiprazole in patients with schizophrenia.
Inclusion Criteria: * Male or female inpatient or outpatients, ages 18-65 Exclusion Criteria: * Participation in a clinical trial of another drug including olanzapine or aripiprazole within 30 days prior to study entry (visit 1). * Treatment with clozapine within the past 12 months. * Have known uncorrected narrow-angle glaucoma. * Have a diagnosis of Parkinson's disease, dementia or related disorder