This Article focuses on one highly complex relationship, that of physician and patient. That relationship, together with the related imperative of protecting patient information, constitutes a crucial component of the legal domain applicable to our most highly regulated industry. Recent inquiries into the trust and confidence properties of the physician-patient relationship and the protection of patient data concentrated on the technical (diagnostic, pharmacy, etc.) data associated with the care relationship. Thus, questions have been asked about the adequacy of protection for networked or interoperable electronic records. ' Such inquires have escalated as patients have been encouraged to leverage technology to store their own "personal" health records." This Article is less interested in technical medical data and more with social data that implicates health and health-related decision-making. Here, the inquiry is how our legal, ethical, and regulatory models will react as the social network phenomenon overlaps with traditional healthcare relationships and businesses. The analysis draws on the limited extant law dealing specifically with social network interactions and the law and ethics literature dealing with existing computer-mediated interactions between physicians and patients. The legal analysis principally is concerned with privacy and confidentiality constructs, described below as the "Law of Boundaries." The Article explores how participation in online social networks may blur boundaries between personal and professional relationships or commentary, while making available "private" information in what only appears to be a secluded area. The Article also examines the potential for amelioration of risks with the currently under-utilized privacy and security settings provided by the online social networks.