Dangerous wildfire conditions continue to threaten people and ecosystems across the globe and cooperation is critical to meeting the outsized need for increased prescribed burning in wildfire risk reduction work. Despite the benefits of using prescribed fire to mitigate wildfire risks, prescribed fire implementation is still challenging. Collaboration and capacity-building can help address policy and capacity barriers inhibiting prescribed fire. We conducted 53 interviews across four case studies in the western United States where federal land management agencies and cooperative actors are working together to accelerate the implementation of prescribed fire to understand the range of actors and associated roles they play. We found that interviewees identified 67 different organizations spanning local to national scales that played a variety of roles to support prescribed fire implementation, mainly communications, prescribed burn labor, fundraising, burning expertise, and burning on neighboring lands. Many actors did not serve in intentional bridging roles, but they filled key roles in the governance networks necessary to implement prescribed fire. Typologies of actor roles can illuminate potential pathways to addressing capacity constraints in achieving wildfire risk reduction. Yet, in networked governance systems, there is a need to distinguish between those in bridging roles and other types of actors who bring capacities to key governance challenges. The growth of networked partnerships working on wildfire risk reduction is reflective of broader global environmental governance trends of increased reliance on non-government actors and the need to work at larger spatial extents.