In English tort law, there can be no liability in negligence unless the claimant establishes both that they were owed a duty of care by the defendant, and that there has been a breach of that duty. The defendant is in breach of duty towards the claimant if their conduct fell short of the standard expected under the circumstances. General standard of care is as follows For a defendant to be deemed negligent, he must have breached his duty of care towards the plaintiff. In order to be deemed as breaching the duty of care, his actions must be proven to fall below the standard of care likely to be taken by the reasonable man. Establishing a breach of duty and ascertaining the standard of care is complex and before establishing that the duty of care has been breached the plaintiff must first prove that the defendant owed him a duty of care. The standard of care is defined as the measures that a reasonable person (in the circumstances of the defendant) take to reduce the risk of harm. This is an objective standard where the 'reasonable person' test is applied to determine if the defendant has breached their duty of care. In other words, it is the response of a reasonable person to a foreseeable risk. The standard of care naturally varies over time, and is affected by circumstantial factors. Thus, when a standard of care is established in one case, it will not automatically become a precedent for another - each case is judged on its own facts. Special standards The standard of "the man on the Clapham omnibus" is not applied in all cases, since this might lead to unfairness. There are defendants for whom this standard is much too low and would exonerate an obvious wrongdoing. In other cases, the standard may be seen as too demanding of the defendant in the circumstances. The most common examples are the cases of specialist defendants, inexperienced defendants and child defendants. Skilled defendants (specialists) The test of an ordinary average person would not be appropriate for defendants that profess or hold themselves out as professing a certain skill. The "man on the Clapham omnibus" does not have that skill and the conduct expected from a skilled professional is not the same as could be expected of an ordinary man in the same circumstances. The general standard applied to professionals