This part introduction presents key concepts discussed in the subsequent chapters. The part covers the basic aspects of evidence-based medicine (EBM) (relating to its definition and practice) and its tangible effects. The paradigm of decision-making under EBM is ensuring the most effective care for the individual. EBM makes explicit the desire to feature the use of published literature in decision-making. EBM is a product of the information age. Its application is technology dependent and co-exists with the development of information systems. The existence of relatively inexpensive data retrieval systems and computers has lessened the costs of making information available, and harnessing it – through protocols – for medical and clinical practice. The trends towards EBM have been enhanced by the new managerialism and emphasis on rationality in health services. The application of managerial techniques to the management of medicine is apparent in many health care systems.