Medication errors are likely the most common safety problem in primary care, and ensuring accurate medication reconciliation remains a challenge in the outpatient setting. This innovative cluster-randomized trial, conducted in a health system with integrated electronic medical records (EMRs), used a novel method of engaging patients in safety to attempt to reduce medication error risk. Patients in the intervention completed their own medication lists, which could then be viewed and reconciled within the EMR by their physicians. Patients who participated had a lower incidence of medication discrepancies and fewer potential adverse drug events than control patients. Although preliminary, the study results point toward further ways in which EMRs can enhance safety by improving patient–physician communication.