This introduction explores the critical role of Advanced Computing and Software in the U.S. Department of Defense’s strategy to maintain national security and military superiority. The chapter explains the role of the following chapters within the broader context of evolving warfare, where digital, cyber, and autonomous systems reshape the battlefield and demand rapid innovation. It outlines the Department of Defense’s identification of 14 critical technology areas, with a focus on Advanced Computing and Software, including big data, artificial intelligence, modeling and simulation, and secure software delivery. Ultimately, this chapter frames the foundation for the book: showcasing women leaders who are shaping the future of defense through innovation in advanced computing and software.