Renewables such as wind and solar are becoming increasingly cost-competitive and are being rapidly deployed to meet decarbonization goals and growing customer and corporate demand for clean energy. At the same time, these resources tend to be located farther away from load centers—in areas where the wind blows hard or the sun shines bright. Transmission is therefore becoming increasingly important to integrate renewables onto the grid and ensure a reliable, affordable clean electricity system. Yet developing new transmission is often slowed down by complex planning and permitting processes, cost allocation issues, and/or legal challenges—with long interconnection queues and network upgrade costs delaying many new wind and solar resources from coming online. What solutions are available to facilitate new transmission development? What opportunities are there to boost existing transmission capacity? What are the roles of policymakers versus the private sector?