This article explains how traditional distribution-grid planning is no longer sufficient as utilities face rapid growth of distributed energy resources, new technologies, and evolving customer and policy demands. It presents Integrated Distribution System Planning (IDSP) as a holistic, transparent approach that combines engineering analysis, cost-risk evaluation, and broad stakeholder engagement to guide grid modernization. By integrating state and utility objectives with customer needs, IDSP helps utilities better anticipate uncertainty, compare traditional and non-wires solutions, and coordinate investments across distribution, transmission, and interregional systems. This ultimately strengthens reliability, resilience, efficiency, and equity in utility regulation and planning.