For someone to be liable of negligence, a duty of care is owed. This is established by the Caparo v Dickman test of foreseeability, proximity, and fair, just and reasonableness/public policy.
Factors that can override proximity, such as in Hill v Chief Constable of West Yorkshire where the police owed no duty of care to the victim's family due to insufficient proximity
Time of alleged breach (Roe v Minister of Health), likelihood of harm (Bolton v Stone), seriousness of foreseeable harm (Paris v Stepney Borough Council), usefulness/importance of defendant's job (Watt v Hertfordshire), cost of avoiding harm (Latimer v AEC)
The breach of duty must be the cause of the damage suffered by the claimant, established through factual causation (but-for test) and legal causation (remoteness of damage)
The defendant takes the claimant as they find them, and cannot avoid liability for greater damage due to the claimant's special sensitivity (Smith v Leech Brain & Co Ltd 1961)