Policy-makers ideally pursue well-informed, socially just means to make environmental decisions. Indigenous peoples have used Indigenous knowledge (IK) to inform decisions about environmental management for millennia. In the last 50 years, many western societies have used environmental assessment (EA) processes to deliberate on industrial proposals, informed by scientific information. Recently EA processes have attempted to incorporate IK in some countries and regions, but practitioners and scholars have criticized the ability of EA to meaningfully engage IK. Here we consider these tensions in Canada, a country with an economic focus on resource extraction and unresolved government-to-government relationships with Indigenous Nations. In 2019, the Canadian government passed the Impact Assessment Act, reinvigorating dialogue on the relationship between IK andEA. Addressing this opportunity, we examined obstacles between IK and EA via a systematic literature review and qualitative analyses of publications and the Act itself. Our results and synthesis identify obstacles preventing the Act from meaningfullyengagingIK, some of which are surmountable(e.g., failures to engage best practices, financial limitations), whereas others are substantial(e.g., knowledge incompatibilities, effects of colonization). Finally, we offer recommendations for practitioners and scholars towards ameliorating relationships between IK and EA towards improved decision-making and recognition of Indigenous rights.