Electric companies are increasingly recognizing that an integrated system planning process across generation, transmission, distribution, and customer end-use resources may provide a more cost-effective and reliable power system than planning individual parts of the system in isolation. This is particularly true for decarbonizing power systems with higher levels of variable renewable energy, energy storage, and distributed energy resources. While a more integrated approach can help identify robust portfolio solutions, the multi-disciplinary nature of the effort requires a deeper understanding of how the different components of integrated planning work together and can be applied.