Systems Engineering is an interdisciplinary field of engineering that focuses on how to design and manage complex engineering systems over their life cycles. System engineers are typically responsible for ensuring system requirements are met and systems are reliable. In addition, they must manage system logistics, coordinate different teams, test and evaluate, while also maintaining systems to ensure successful system development, design, implementation, and ultimately the decommission of a system. These job duties become more difficult when dealing with large or complex projects. System engineers also deal with work-processes, optimization methods, and risk management tools during projects. Their job usually overlaps technical expertise with human-centered disciplines such as control engineering, industrial engineering, software engineering, organizational studies, and project management. Systems engineering ensures that all likely aspects of a project or system are considered, and integrated into a whole.