Gen. Stilwell, who also had operational command of the Northern Combat Area Command (NCAC), a US-Chinese formation, was to report in theory to Gen. George Giffard – commander of Eleventh Army Group – so that NCAC and the British Fourteenth Army, under the command of General William Slim, could be co-ordinated. However, in practice, Gen. Stilwell never agreed to this arrangement. Stilwell was able to do this because of his multiple positions within complex command structures, including especially his simultaneous positions of Deputy Supreme Allied Commander South East Asia, and Chief of Staff to Chinese leader Generalissimo Chiang Kai-shek. As SEAC's deputy leader, Stilwell was Giffard's superior, but as operational commander of NCAC, Giffard was Stilwell's superior. As the two men did not get on, this inevitably lead to conflict and confusion.