In this paper, and via a case study in Waterloo, we explore policy's role in encouraging green infrastructure (GI) adoption in Ontario universities. More specifically, we evaluate the relationship between policy and GI, and determine the policy level required to successfully implement GI. We employed a qualitative research approach of semi-structured, open-ended interviews (n = 8) to understand better participants' views towards existing GI policies and frameworks. We find that multi-level government collaboration, regulatory frameworks and incentives and funding mechanisms are key themes influencing GI adoption. Interviews revealed that municipal incentives are essential in encouraging GI implementation on a local scale. However, federal and provincial factors are also crucial for the long-term establishment of GI. We conclude that policy is essential, and that multi-level collaboration is required to implement GI across Ontario's universities. With little published research there is in this area suggests the importance of government policy, especially at the municipal level, in terms of getting GI projects built. Yet, there are key gaps in our understanding, including the role of provincial and federal policy.