This article explores the impact of Afghanistan’s borderlands on the politics of center-periphery relations in Afghanistan during the security transition in 2014. The article discusses the developments in Afghanistan’s borderland regions by examining the characteristics of its border areas with Pakistan and Iran, as well as with the Central Asian states and China. The article argues that there are grounds for cautious optimism concerning the capacity of Afghanistan’s central government to strengthen its political authority over these areas in the aftermath of the security transition in 2014, if Afghanistan’s borderlands are more closely integrated into the post-2001 process of state-building, and if Afghanistan’s borders with all of its neighbors are adequately secured.