Traditionally abundant reserves in the system have been eroded due to the increased penetration of variable resources, potentially impairing system reliability. To operate the power system with leaner reserve margins, distributed generation resources need to participate in maintaining or improving system resiliency and reliability. This requires new control and protection coordination systems, along with supporting communication networks. This is a revolution in how the power system is planned and operated, relying more heavily on hierarchical and distributed control architectures with greater dependency on a variety of communication media. Co-simulation and integrated planning of transmission, distribution, and communication systems (along with markets and other elements) allows planners to understand the bottlenecks and pitfalls of the interplay between power and communication systems to ensure safe and reliable operations; enable informed decisions on investments at multiple levels; and allow exploration of future scenarios in a wide variety of applications such as DER integration and distributed control. This panel will discuss current and future trends in this area, including utility experiences, example use cases, and ongoing development efforts.