Despite growing support for patient involvement in safety and quality improvement, little is known about engaging patients as partners in reducing diagnostic error. This commentary summarizes research on how sharing notes with patients can improve the timeliness of follow-up to confirm a diagnosis, identify documentation errors, and strengthen communication between the clinical team and the patient. The authors discuss challenges to the successful implementation of this strategy and areas of focus needed for future development. A PSNet interview discussed use of OpenNotes to engage patients in their care.