As internet access and the use of mobile devices becomes more widely available, and as it is increasingly used by patients to access health information, many healthcare systems are capitalizing on this trend by offering patients electronic methods to communicate with providers and to learn about their health and medical problems. Some organizations or practices have developed stand-alone systems that allow for secure messaging between patients and their providers. Others, particularly those with existing electronic health record systems (EHRs), are developing companion applications specifically designed for patients that give patients access to email communication, access to their medical records and to test reports, and access to educational information on preventive care or disease-specific care. Much of this development is based on a perception that this is something that patients desire; and, that these systems will enhance patient satisfaction, improve care or make it more efficient. As the Veterans Health Administration (VHA) expands the capabilities of its personal health record system, My HealtheVet (MHV), and places greater emphasis on encouraging its use, it is interested in understanding how best to prioritize different functionalities and which of them will provide the greatest benefits to Veterans. This systematic review was designed to evaluate the literature surrounding secure messaging systems and electronic applications that give patients access to their own medical records, specifically investigating the evidence that these systems improve health outcomes, patient satisfaction, healthcare utilization and efficiency, and adherence. Additionally, the review examined studies that evaluated attitudes, particularly regarding patients having online access to their own medical information; and specific patient characteristics associated with use of personal health record systems. The review distinguished between electronic systems that were "tethered" or tied to existing healthcare institution systems similar to how MHV is tethered to VHA's EHR, versus those that were "stand-alone." The key questions were: Key Question #1. What is the association between secure messaging and health outcomes, patient satisfaction, adherence, efficiency or utilization, or automated email? Key Question #2. What is the association between patient access to their own medical record and health outcomes, patient satisfaction, adherence, efficiency or utilization, and attitudes about access?