Safety issues are common in the ambulatory care setting, but they can be difficult to detect because patients may spend months between contacts with the health care system. Engaging patients in their care is a recommended strategy to improve ambulatory safety and is the focus of a recent AHRQ toolkit. The OpenNotes initiative—in which patients have the opportunity to review and edit their medical records contemporaneously—aims to improve patient engagement and patient safety through promoting transparency. In this study, patients and caregivers with OpenNotes access were surveyed regarding the perceived effect of accessing notes on their understanding of their medical conditions and the patient–clinician relationship. Overall, most participants felt that accessing OpenNotes facilitated their understanding of the rationale for tests and referrals and improved their relationship with primary care providers. Although hindered by a low response rate, this study provides some support for the proposition that increased transparency can enhance patient engagement.