Medicine is becoming more complex and every work is difficult to manage and process. Advances in medical imaging have made it possible to get accurate information about patient condition quickly and easily. Patient examination may include traditional X-ray (radiography), fluoroscopy, computed tomography (CT), ultrasound, nuclear medicine, or magnetic resonance imaging (MRI) or even image fusion using various imaging modalities like (PET/CT) or PET/MRI.Improved technology and more complex treatments in modern radiotherapy can only be fully exploited if a high level of accuracy and consistency is achieved through efficient Database Management System.The need for compressing data comes up for archiving and telemedicine applications where storage space and low bandwidth could make it impossible for an efficient data processing and transmission services. Lossy compression algorithms could be a solution. Medical physicists are greatly involved in the administration and data base management of this complex system. Information needs to be robust and available in real time. Dose monitoring has to be systematically managed following ALARA principle. All of these are expressed in this book.