The Historical Foundations of the Duty of Care PlunkettJames C 2019 The duty of care serves a valuable function in the law of negligence: it specifies when damage caused by another’s carelessness becomes actionable. This article explores how this valuable function, central to the analysis of liability for negligence, came to be served by the idea of a ‘duty of care’. The article first traces the evolution of the duty of care from its earliest beginnings to the point at which it became fixed as an element of the developing action for negligence. The article then explores the judiciary’s development and articulation of the duty concept. In particular, it examines how the courts developed tests for the scope and content of a duty, how it came to be a duty of care, and how the existence of such a duty came to be based on the idea of foreseeability.