This chapter examines the linkages between Indigenous Data Sovereignty (IDS), self-determination and policy, focusing on Aotearoa NZ. We ask how policy can realize the transformative potential of IDS to support Māori aspirations for self-determination. Our central argument is that the fullness of IDS cannot be realized within the architecture of the colonial settler state. However, there is scope for policy to support Māori and iwi (tribal) nations and communities to develop and control our own data systems. We discuss these and what we see as the transformations needed to move from data dependency to data sovereignty.