Application modernization challenges include technical debt, legacy architecture, security vulnerabilities, cloud migration complexity, integration issues, skills shortages, and organizational resistance. Enterprises can overcome these challenges through phased modernization, cloud-native architecture, automation, DevSecOps, and a well-defined modernization roadmap aligned with business objectives. Introduction Application modernization has become a strategic priority as organizations strive to reduce technical debt, accelerate software delivery, strengthen security, and adopt cloud-native architectures.