Urban systems draw on food, energy, and water outside of their physical boundaries, and create environmental impacts which extend beyond city borders. All three of these resources face growing demand, supply constraints, and are of substantial importance to a sustainable world. Our world is increasingly urbanized, with cities having large and concentrated environmental impacts, but also the opportunity to implement unique sustainability solutions at scale. The interactions between food, energy, and water are best captured through a nexus view, identifying the full interactions between these resources. Topics of growing significance to urban systems are identified with their nexus connections. These connections facilitate complex sustainability challenges, but also can also be harnessed to promote coordinated solutions.