The demand for transit across the U.S. is growing, and more and more transit corridors are proposed and built each year. With so many stations opening, there is a growing need to understand how corridor planning can facilitate not only successful transportation outcomes but also successful transit-oriented development (TOD). All scales of planning for TOD are important, but planning at the corridor level can be a more efficient way to achieve the benefits of TOD at all stations along the corridor. Corridor planning can provide a cost effective process, especially when multiple stations along a corridor face similar challenges and opportunities. The corridor is also the best scale at which to predict the long-range impacts of transit on the market for new development, on commuter travel behavior, and on where the potential for displacement of low-income residents may be greatest. Corridor planning presents an enormous opportunity to engage stakeholders early in the process.