Online access to medical records and linked services, including requesting repeat prescriptions and booking appointments, enables patients to personalize their access to care. However, online access creates opportunities and challenges for both health professionals and their patients, in practices and in research. The challenges for practice are the impact of online services on workload and the quality and safety of health care. Health professionals are concerned about the impact on workload, especially from email or other online enquiry systems, as well as risks to privacy. Patients report how online access provides a convenient means through which to access their health provider and may offer greater satisfaction if they get a timely response from a clinician. Online access and services may also result in unforeseen consequences and may change the nature of the patient-clinician interaction. Research challenges include: (1) Ensuring privacy, including how to control inappropriate carer and guardian access to medical records; (2) Whether online access to records improves patient safety and health outcomes; (3) Whether record access increases disparities across social classes and between genders; and (4) Improving efficiency. The challenges for practice are: (1) How to incorporate online access into clinical workflow; (2) The need for a business model to fund the additional time taken. Creating a sustainable business model for a safe, private, informative, more equitable online service is needed if online access to records is to be provided outside of pay-for-service systems.