Individuals care about and guard their privacy intensely in many areas. With respect to patient medical records, people are exceedingly concerned about privacy protection, because they recognize that health care generates the most sensitive sorts of personal information. In an age of advancing technology, with the switch from paper medical files to massive computer databases, privacy protection for medical information poses a dramatic challenge. Given high-speed computers and Internet capabilities, as well as other advanced communications technologies, the potential for abuse is much greater than ever before. At every stage in the process of collection and storage, dangers can arise, including entry errors, improper access, exploitation, and unauthorized disclosure. Secondary use and aggregation of data are all far easier, faster, and less expensive, and thus pose additional threats to an individual's control over the disposition of medical information.