As the number of transboundary conservation initiatives continues to grow in response to the twin threats of climate change and biodiversity loss, so too have calls for Indigenous-led conservation that recognizes Indigenous rights and supports Indigenous land and wildlife stewardship. And yet, because many transboundary initiatives have historically been settler-led, such efforts are now contending with how best to pivot toward models of more meaningful Indigenous engagement and leadership. Here, we describe the Cascadia Partner Forum’s recently completed Blueprint for a Resilient Cascadia, a collaborative strategy for supporting large-landscape resilience in the transboundary region of Washington and British Columbia. We reflect on the history of the Cascadia Partner Forum, the collaborative process employed in its development of the Blueprint for a Resilient Cascadia, and its commitment and ongoing effort to ethically and effectively engage with Tribes and First Nations. We pay particular attention to a transformational shift that occurred during Blueprint development: a move from an initial goal of “Indigenous engagement” toward one of “centering Indigenous leadership,” and describe the resulting effort to provide a space for leadership by Tribes and First Nations while supporting the capacity such leadership requires. We hope our reflections can help inform other transboundary conservation initiatives working to move away from what has been a predominantly colonizing model of conservation to one promoting Indigenous-led governance.