Legacy application modernization is a complex process that organizations undertake to balance business continuity with adopting modern technologies. The text outlines the challenges associated with legacy systems, such as outdated documentation, knowledge gaps, and dependencies on obsolete technologies, which make full system rewrites risky and often unsuccessful. It advocates for incremental migration strategies, which allow organizations to transform legacy systems progressively while minimizing risk and delivering business value. Key approaches include the strangler fig pattern, encapsulation, decomposition, and parallel implementation, each offering different benefits and suited to specific scenarios. These strategies enable organizations to modernize at a sustainable pace without disrupting operations, focusing on business outcomes rather than just technical changes. The article emphasizes the importance of thorough assessment, robust CI/CD capabilities, and organizational structures, such as team models and skills development, to support the modernization journey. It underscores the need for effective governance and risk management practices to ensure a successful transition, ultimately enabling legacy applications to evolve into modern systems that enhance business agility and innovation.