Increased use of e-mail by physicians, patients, and other health care organizations and staff has the potential to reshape the current boundaries of relationships in medical practice. By comparing reception of e-mail technology in medical practice with its historical analogue, reception of the telephone, this article suggests that new expectations, practice standards, and potential liabilities emerge with the introduction of this new communication technology. Physicians using e-mail should be aware of these considerations and construct their e-mail communications accordingly, recognizing that e-mail may be included in the patient's medical record. Likewise, physicians should discuss the ramifications of communicating electronically with patients and obtain documented informed consent before using e-mail. Physicians must keep patient information confidential, which will require taking precautions (including encryption to prevent interception) to preserve patient information, trust, and the integrity of the patient-physician relationship.