The United States, like many countries across the world, is transitioning from energy markets that rely heavily on fossil fuel resources to those that increasingly rely on low-carbon, efficient, and advanced energy resources. The potential benefits of this transition are significant. This transition, however, will not be just if the burdens are disproportionately received by certain populations, if populations are excluded from the new opportunities it provides, or if decision-making processes are not accessible to all. In this chapter, we define a just transition and discuss the dimensions of a just transition in the U.S. context. We examine the role of government in a just transition, as well as the current state of knowledge about how well energy justice policies work and how far they extend. We conclude with a call for future studies to build more information about this important topic.