This study examines the role of sub-national diplomacy in India with respect to four neighboring countries - Sri Lanka, Bangladesh, Pakistan and China - and assesses the nature and consequences of such interactions for immediate policy shifts and in wider institutional terms. Except for five states - Haryana, Jharkhand, Madhya Pradesh, Chhatisgarh and Telengana - all other states in India have international land or maritime borders which make a study of this nature very pertinent. This study focuses on those states that have been more inclined to engage in India's foreign and security policy making.