In English tort law, an individual may owe a duty of care to another, to ensure that they do not suffer any unreasonable harm or loss. If such a duty is found to be breached, a legal liability is imposed upon the tortfeasor to compensate the victim for any losses they incur. The idea of individuals owing strangers a duty of care – where beforehand such duties were only found from contractual arrangements – developed at common law, throughout the 20th century. The doctrine was significantly developed in the case of Donoghue v Stevenson, where a woman succeeded in establishing a manufacturer of ginger beer owed her a duty of care, where it had been negligently produced. Following this, the duty concept has expanded into a coherent judicial test, which must be satisfied in order to claim in negligence.