Over the past two decades, there have been some fundamental changes in the practice of radiology and in medical imaging technology. Besides the broad adoption of advanced imaging technologies such as magnetic resonance imaging (MRI), positron emission tomography (PET), and computed tomography (CT), the complete transition of all imaging modalities to digital format has brought about some profound changes in medical imaging, which have led to paradigm changes in overall patient care. These revolutionary changes include the introduction and broad use of picture archiving and communication systems (PACS) and the adoption of electronic health record (EHR) systems which have dramatically changed the workfl ow in healthcare organizations and the procedures for image interpretation and communication among healthcare providers and patients. Over the past 10-15 years, the adoption of digital imaging and PACS, along with EHRs and other clinical information systems such as radiology information systems (RIS) and hospital information systems (HIS), has dramatically increased the effi ciency of patient care. In this book, the essential principles of PACS, EHRs, and related technological advancements are discussed, together with practical issues concerning the implementation, operation, and maintenance of PACS and EHR systems.