This Practice Note deals with establishing the causal link of whether the breach caused the injury to the claimant. It also covers complications in establishing causation in the context of diseases, loss of a chance, multiple tortfeasors, combined causes, consecutive cases, vicissitudes of life and new intervening acts. The court will start by asking ‘but for’ the defendant’s negligence, would the claimant have sustained their injuries? This is a question of fact and in many cases the answer will be simple and conclusive. Where another cause also contributed to the claimant’s injuries, the court may need to decide which was the real or effective cause. This is a question of law. A common issue for the court is whether the chain of causation was broken by an intervening act or event.