In recent years, electric utilities have seen a rapid increase in the deployment of small-scale, grid-connected distributed energy resources (DERs) – including energy efficiency, demand response and flexible loads, distributed generation (primarily solar photovoltaic systems), energy storage systems, and electric vehicles. Deployment of these DERs is expected to increase in coming years. In most cases, the utilities do not own or control these DERs, and in some cases they do not even have knowledge of the DER’s existence, location, capabilities, and status (i.e., “visibility”).These trends are leading to new challenges for utilities in planning their infrastructure investments and managing power quality at the level of the distribution system. The challenges are distinctly different from the large-scale generation and transmission challenges in regional planning processes. A few jurisdictions in the US have begun experimenting with integrated distribution planning mechanisms that seek to methodically anticipate such challenges and find least-cost solutions for addressing them.This presentation for the Mid-Atlantic Distributed Resources Initiative covers integrated distribution planning concepts and ways state public utility commissions are engaging in long-term distribution system planning.