Efficiency is often overlooked as an ethical value and seen as ethically relevant chiefly when it conflicts with other values, such as equality. This article argues that efficiency is a rich and philosophically interesting concept deserving of independent normative examination. Drawing on a detailed healthcare case study, we argue that making assessments of efficiency involves value-laden, deliberative judgments about how to characterize the functioning of human systems. Personal and emotional resources and ends are crucial to system functioning but are often discounted in favor of a relatively narrow set of financial inputs and institutional or procedural outputs. Judgments about efficiency tend to advantage (or disadvantage) different parties, depending on the resources and ends considered. Different constructions of efficiency can therefore promote or neglect the perspectives and interests of differently placed actors. Models of efficiency do not merely embody contestable ethical standpoints but-put to use-can unwittingly reify and reproduce them.