Contingency Management of Psychostimulant Abuse in the Severely Mentally Ill

Inclusion Criteria: * Enrolled patient at Community Psychiatric Clinic (CPC), a large mental health center in urban Seattle, Washington; * Between 18 and 65 years of age; * Diagnosis of of methamphetamine, amphetamine(illegal), or cocaine dependence or abuse; * CPC medical record diagnosis of schizophrenia, schizoaffective disorder, bipolar I or II, or recurrent major depressive disorder * Stimulant drug use one month before enrollment; * Ability to understand written and spoken English; * CPC clinical case manager must affirm the potential participant's ability to provide informed consent and clinical appropriateness (i.e., safety/severity of mental/substance/ physical health) to participate in the study. Exclusion Criteria: * Any medical/psychiatric condition, or severity of that condition, that, in the opinion of Dr. Ries, the PI, would compromise safe study participation * Chart defined organic brain disorder or dementia; * Current participation in a methadone maintenance program; * Any other circumstances that in the PI's opinion precludes safe study participation.