Inclusion Criteria:

• Must have primary DSM-IV diagnosis of Schizophrenia or Schizoaffective disorder
• Must have DSM-IV diagnosis of current cocaine dependence
• Self-report cocaine use in the last 90 days
• Are capable of reading, comprehending and signing informed consent
• Agree to take Aripiprazole or Perphenzine as treatment for SCHZ and CD
• Agree to stop taking any other antipsychotic medication
• If female and of child bearing potential, agree to use an acceptable form of birth control and have a negative pregnancy test within 2 days prior to starting study medication

Exclusion Criteria:

• Under 18 years old or over 65 years old
• Refusal or inability to give informed consent
• Have a history of myocardial infarction or ischemic heart disease, heart failure or conduction abnormalities, cerebrovascular disease, or conditions that would predispose to hypotension
• A history of seizures or conditions that lower the seizure threshold
• Have current suicidal ideation (history of suicide attempt in past 60 days)
• Have current dependence, defined by DSM-IV criteria, on any psychoactive substance other than cocaine, alcohol, nicotine or marijuana, or psysiological dependence on alcohol requiring medical detoxification
• Are actively psychotic which in the opinion of the investigator would preclude proper informed consenting or protocol adherence
• Are receiving or plan to receive an agent metabolized by the Cytochrome P450-3A4 or -2D6 systems, including carbamazepine, ketoconizole, quinidine, fluoxetine, and paroxetine
• Woman of child bearing potential not on, or do not agree to use an acceptable form of contraception
• Known sensitivity to aripiprazole or perphenazine
• A diagnosis of current of past tardive dyskensia
• Pending legal charges or a court mandate for drug treatment
• Currently taking concomitant medications that have been shown to reduce cocaine use.
• Clinically significant liver function abnormalities
• Currently receving depot neuroleptics