Objective. To identify clinically useful predictors of adherence to medication among persons with schizophrenia. Method. We evaluated levels of compliance with neuroleptic medication among 32 consecutive admissions with DSM-III-R schizophrenia from a geographically defined catchment area using a compliance interview. We also assessed symptomatology, insight, neurological status and memory. Results. Less than 25% of consecutive admissions reported being fully compliant. Drug attitudes were the best predictor of regular compliance, symptomatology the best predictor of noncompliance, and memory the best predictor of partial compliance with neuroleptic medication. Conclusions. These data emphasise the complexity of factors that influence whether a person adheres to his medication regimen. Furthermore, they suggest that these factors may vary within the same person over time.