▁took ▁place ▁from ▁ 4 ▁to ▁ 1 1 ▁November ▁at ▁the ▁O 2 ▁Arena ▁in ▁London , ▁United ▁Kingdom . ▁It ▁was ▁the ▁ 4 4 th ▁edition ▁of ▁the ▁tournament ▁( 3 9 th ▁in ▁doubles ). ▁The ▁tournament ▁was ▁run ▁by ▁the ▁Association ▁of ▁Tennis ▁Prof ession als ▁( AT P ) ▁and ▁was ▁part ▁of ▁the ▁ 2 0 1 3 ▁ATP ▁World ▁Tour . ▁The ▁event ▁took ▁place ▁on ▁ind oor ▁hard ▁courts . ▁It ▁served ▁as ▁the ▁season - ending ▁champion ships ▁for ▁players ▁on ▁the ▁ATP ▁Tour . ▁The ▁eight ▁players ▁who ▁qualified ▁for ▁the ▁event ▁were ▁split ▁into ▁two ▁groups ▁of ▁four . ▁During ▁this ▁stage , ▁players ▁competed ▁in ▁a ▁round - ro bin ▁format ▁( mean ing ▁players ▁played ▁against ▁all ▁the ▁other ▁players ▁in ▁their ▁group ). ▁The ▁two ▁players ▁with ▁the ▁best ▁results ▁in ▁each ▁group ▁progress ed ▁to ▁the ▁semif inals , ▁where ▁the ▁w inners ▁of ▁a ▁group ▁faced ▁the ▁run ners - up ▁of ▁the ▁other ▁group . ▁This ▁stage , ▁however , ▁was ▁a ▁knock - out ▁stage . ▁The ▁doubles ▁competition ▁used ▁the ▁same ▁format . ▁ ▁Format ▁ ▁The ▁Bar cl ays ▁ATP ▁World ▁Tour ▁Final s ▁had ▁a ▁round - ro bin ▁format , ▁with ▁eight ▁players / te ams ▁divided ▁into ▁two ▁groups ▁of ▁four . ▁The ▁eight ▁se eds ▁were ▁determined ▁by ▁the ▁ATP ▁Rank ings ▁and ▁ATP ▁Dou bles ▁Team ▁Rank ings ▁on ▁the ▁Monday ▁after ▁the ▁last ▁ATP ▁World ▁Tour