Nuclear Power Plants (NPPs) have been closing in some parts of the country due to the impacts of adverse market conditions, placing an increased emphasis on Operating and Maintenance (O&M) cost reductions. Concurrent with these market conditions, increased capital spending is needed to address obsolete systems and components. Upgrading outdated Instrumentation and Control (I&C) systems to digital is considered an effective approach for reducing the O&M costs and increasing plant reliability. As most operating plants in the U.S. have already extended their license to 60 years, and Subsequent License Renewals planned for eighty-year licenses, upgrade of the outdated I&C technology is becoming increasingly important. Often DI&C upgrade projects have been plagued with negative cost and schedule impacts that may have been avoided with more thorough upfront planning. The procedure infrastructure, Distributed Control System (DCS) Platform Selection, DI&C Architecture, Licensing Strategy and Diversity and Defense-in-Depth Strategy are all important factors to evaluate prior to launching major digital upgrades. Digital upgrades bring new requirements and capabilities that if not well understood, can and have resulted in additional scope growth late in the design process. Proper planning is an important factor in ensuring the project meets all functional, schedule, and cost requirements as well as ensuring the new technology capabilities are fully utilized.