The purpose of this quality improvement project was to re-align the standard of psychiatric care with best practices for nine clients with co-occurring mental illness and intellectual disability (ID) in an Oregon community mental health center. For three months, a Psychiatric-Mental Health Nurse Practitioner who specialized in Developmental Disability Psychiatry sought to decrease same-class polypharmacy, and benzodiazepine use. A standardized tool, the Aberrant Behavior Checklist (ABC), was used to assess impact of medication changes on behavior problems. Caregivers answered a question comparing the attentiveness of the specialized PMHNP compared to the attentiveness of previous psychiatric providers. Data were analyzed using descriptive statistics, Wilcoxon signed-rank tests, and 1-sample t-tests.