Chronic abuse of drugs from various pharmacological classes can produce psychoses that are indistinguishable from symptoms associated with schizophrenia. A well-characterized example of this is amphetamine-induced psychotic disorder. In laboratory settings, the use of pharmacologically-induced models of psychosis has greatly improved our understanding of psychosis and aided in identifying mechanisms beyond dopamine antagonism that may increase antipsychotic efficacy. This symposium will address the role of serotonergic, glutamatergic, and cannabinergic neurotransmitter systems in mediating or attenuating aspects of psychosis, and provide a current review of pharmacologically-induced models of psychosis.