[2005] EWHC Civ 1151, 10 October 2005. Considered whether two separate employers could both be vicariously liable for the negligence of a single employee. V had engaged T to install air conditioning in V's factory. T subcontracted ducting work to D, who then contracted with H to provide fitters and labourers. A fitter's mate, supplied by H but under the overall supervision of a fitter contracted to D, negligently caused a flood. The judge found that H, but not D, was vicariously liable for the negligence. H appealed, on the basis that dual vicarious liability was not legally possible, and that D alone was liable. D argued that H was solely liable, but that dual vicarious liability was a legal possibility. "Held": Vicarious liability was determined by who had been entitled to exercise control over the fitter's mate. The key question was who bore responsibility to prevent his negligent act by being entitled and obliged to give orders as to how the work should be done. On the facts, both H's and D's fitters had been entitled, and obliged, to prevent the mate's negligence. Contrary to the assumption held since the early 19th century, dual vicarious liability was legally possible; in this case both H and D were vicariously liable for the mate's negligence, and if they had dual control of the employee, the measure of control was equal, and it was therefore just and equitable to divide liabilty between them on an equal basis.