Capacity building is needed to enable effective and inclusive governance of emerging climate intervention technologies. Here we use solar geoengineering (SG) as a case of an emerging climate intervention technology to highlight the importance of focusing attention on building capacity to govern these and similar technologies. We propose the concept of “governance capacity building” to help focus research and practice toward building and strengthening the knowledge, skills, tools, practices, or resources needed to govern SG. Centrally, we argue that “governance capacity building” is needed to enable multiple types of actors to contribute to all stages of the governance process, should be owned by recipients, and aimed toward building long term and durable forms of capacity. These capacity building efforts must center climate vulnerable communities and countries that stand to gain or lose the most from decisions about whether and how research and deployment of these technologies will move forward. To ensure governance capacity remains with these populations over the long term, governance capacity building should embrace a new model of capacity building envisioned primarily by actors in the Global South. We use these insights to demonstrate that gaps and limitations in how capacity building is understood in the SG governance literature and implemented in practice are stifling the potential for capacity building to enable effective and inclusive governance in the SG issue area. To help rectify this, we chart a path toward building successful governance capacity building programs for climate intervention technologies.