This book provides a comprehensive investigation of the change requirement management in the modern software industry, which uses agile methodologies while adhering to the concept of software as a service. In agile methodologies, as depicted in the agile manifesto customer involvement is essential and their feedback is considered in the final product development. The clients' requirements in the modern world changing rapidly. Therefore, the project requirements initially fixed are always history. Thus, even after the successful completion and the delivery of the products, the software companies usually agreeing to do the required changes based on the user personas and the dependencies of the system environments upon further agreements. At this point, new requirements of the system begin to evolve in addressing new business needs and usability study results. As a result, the project scope may be extended than initially expected. To facilitate the aforementioned scenario, this bookprovides useful insights to software practitioners to simplify the identification of Bugs and Change Requirements.