The prescribing and administration of clozapine as well as monitoring requisites for patients on clozapine therapy is distinctly different from other antipsychotic drugs. This study evaluated a Clozapine Decision Support Tool (CDST) to improve patient outcomes. The CDST was developed, using current clozapine guidelines and published literature. The study was conducted at a long-stay mental health facility and included all 67 patients who were on clozapine therapy during the study period. The study comprised of a pre-and post-intervention audit of clozapine prescribing, with the introduction of the CDST as the intervention, to assess the level of clinician adherence to the clozapine guidelines. There was an overall improvement in clinician adherence to the clozapine guidelines with statistically significant improvements in monthly physical health monitoring and 6-monthly electrocardiography. The results of this study suggest that using the CDST may improve clinician adherence to current guidelines and ultimately improve patient outcomes.