PP&TS are a valuable resource to assist practitioners in providing appropriate radiologic care for patients. These documents are not intended to establish, imply, or reflect “best practice” guidance, but are important to understanding the basic elements in providing quality radiological care. The practice of medicine involves not only science, but also the art of dealing with the prevention, diagnosis, alleviation, and treatment of disease. The variety and complexity of human conditions make it impossible to always reach the most appropriate diagnosis or to predict with certainty a particular response to treatment. It should be recognized; therefore, that adherence to these parameters will not assure an accurate diagnosis or a successful outcome. PP&TS are not intended, nor should they be used, to establish a legal standard of care. All that should be expected is that the practitioner will follow a reasonable course of action based on current knowledge, available resources, and the needs of the patient to deliver effective and safe medical care. ACR cautions against the use of these parameters in litigation in which the clinical decisions of a practitioner are called into question.