[2002] UKHL 22, 20 June 2002. Three appeals against CA decisions heard together related to employees who had developed mesothelioma caused by exposure at work to asbestos dust during periods of employment with more than one employer. In two cases the claims were dismissed as it was not deemed possible on the balance of probabilities to establish which defendant was responsible for the harmful exposure; in the third case liability was apportioned between the three defendants. "Held" appeals allowed. Where an employee had been exposed to asbestos by differing employers during differing periods of employment and the onset of disease could not be attributed medically to any particular or cumulative exposure, a modified approach to proof of causation was justified, the claimants proving on a balance of probabilities the necessary causal connection to establish the defendants' liability. View judgment at www.publications.parliament.uk/.