Bangladesh and India are enjoying increasingly close relations in the latter’s northeastern region. This represents a transformation in the two countries’ past relationship, which was characterised by suspicion, distrust and insecurity. This recent change, which began with the arrival of Bangladesh’s current regime in 2009, has resulted in a sense of cooperation, mutual interest and connectivity. This article aims to explain this transformation. The first part of this article presents the traditional sources of insecurity between Bangladesh and India, which resulted in confrontational relations between the two neighbours. The second part then highlights how a convergence of security, economic and energy cooperation has transformed Bangladesh’s relations with India, especially, in its northeastern region.