In his latest book, renowned ethicist James F. Childress uses various metaphors and analogies to highlight the role of imagination in practical reasoning. Childress shows how principles, metaphors, and analogies illuminate moral problems and issues in science, medicine, and health care. The issues he considers include screening and testing for HIV infection, informed consent to and refusal of life-sustaining treatment, allocating scarce health care resources, providing access to and controlling the costs of health care, and obtaining organs and tissues for transplantation.