1. Duty of care
Lord Atkin's neighbour principle in Donoghue v Stevenson [1932] says you must take reasonable care not to injure those you can reasonably foresee being affected by your actions. Caparo v Dickman [1990] later framed new duties around foreseeability, proximity and whether a duty is fair, just and reasonable. Robinson v Chief Constable of West Yorkshire [2018] clarified that courts first apply established categories of duty, and use the Caparo factors only for genuinely new situations.
2. Breach
The defendant breaches the duty by falling below the standard of the reasonable person in their position (Blyth v Birmingham Waterworks (1856)). Courts weigh the likelihood and seriousness of harm against the cost of precautions.
3. Causation
Ask whether the harm would have happened but for the breach. In Barnett v Chelsea & Kensington Hospital [1969] the doctor was negligent, but the patient would have died anyway, so causation failed. A new intervening act (novus actus interveniens) can break the chain.
4. Remoteness
The type of damage must have been reasonably foreseeable (The Wagon Mound (No 1) [1961]). If it was, the defendant is liable even if the extent of the damage was greater than expected.