Increasing usage of ICT in medical organizations raises the issue of information security. This research study focuses on, and analyzes technology and management aspects for, information security of networked medical organizations through a teleradiology case study. A 'workshop' to gauge risk assessment was also established in which stakeholders, such as patients and radiologists, discussed the risk threat inherent in teleradiology. Based on this discussion, technological, organizational, physical, and personal security countermeasures were developed and organizational rules for networked organizations created. We conducted a step-by-step approach in which the second medical organization referred to the first medical organization's process and rules, and found that this approach was both efficient and effective. However, we also discovered that many internal and external adjustment works for each medical organization exist. To solve these issues we proposed two societal functions for audit and supportive institutions to handle such issues as compliance and education.