This chapter constructs a picture of the struggle waged by Indian leaders to negotiate the seemingly contradictory demands of national security and upholding popular conceptions of state sovereignty. Attention is given to the strategies adopted by New Delhi to co-opt the assistance of MI5 in containing Cold War threats, in the guise of indigenous communist movements and external pressures from China and the Soviet Union. Britain’s intelligence agencies made an effort to transition from a role centred on subduing nationalism to that of a trusted and valued supporter of the ruling Congress Party. Establishing strong security and intelligence links with India, British governments rationalised, would help to preserve their considerable national interests in South Asia; keep India ostensibly aligned with the West; act as a barrier to communist penetration of the subcontinent; and demonstrate to the United States that Britain remained a useful post-war partner. However, ideological tensions and differences produced uncoordinated bureaucratic responses that allowed the forces of internal and external communism to claim political and geographic space in the region.