This textbook introduces systems engineering into the Agile Scrum framework for software development. The author first covers the foundations of systems engineering and Agile Scrum in software development, as well as special considerations in software requirements management. The author then explains in detail the need for increased engineering rigor in critical software solutions. To tackle this problem, the author presents Systems Engineering Focused Agile Development (SEFAD). The author presents and discusses SEFAD’s best practices, case studies, and considerations in rigorous software quality assurance. The intent of this book is to educate software and systems engineers on the importance of maintaining a balance in engineering rigor in the software engineering process while also allowing for agility and adaptation. The book includes exercises, student projects, and case studies throughout.