There is not much doubt that information, information services and systems need to be useful. In this light, the relatively lack of conceptual elaboration of the concept of usefulness in the library and information science literature can be regarded as somewhat surprising. This paper provides a conceptual overview of the use of the notion of usefulness in library and information science literature, explicates its relation to key parallel concepts, and on the basis of an empirical vignette in the context of health information research, discusses the potential limits and advantages of referring to usefulness instead of and together with other related concepts. A review of literature relating to the concept of usefulness was conducted to examine how it has been used in library and information science. A close reading of the literature shows an overlap between related concepts but at the same time, diverging foci of interest in and emphasis on what and how information, information services and, for instance, information systems are considered beneficial or suitable for their users and particular uses. There is a need for better conceptual clarity in the literature regarding usefulness and related concepts. The review shows that usefulness can be literally a useful concept for addressing the user and use (versus e.g. system, content or topic) perspective to engagements with people, services, systems and beyond.