Cyber Defense in the Quantum Age: From Classical Security to Quantum Safe Design explores the urgent transition from classical cybersecurity to quantum-safe design. As quantum computing threatens today’s encryption standards, this book provides strategic insight, technical foundations, and practical migration frameworks for building resilient systems. Covering post-quantum cryptography, cryptographic agility, risk management, and policy implications, it equips security professionals, leaders, and researchers to anticipate disruption and design long-term digital resilience. Blending theory with implementation guidance, it prepares organizations to defend against emerging quantum threats and safeguard future digital trust.