The systems architect is an information and communications technology professional. Systems architects define the architecture of a computerized system (i.e., a system composed of software and hardware) in order to fulfill certain requirements. Such definitions include: a breakdown of the system into components, the component interactions and interfaces (including with the environment, especially the user), and the technologies and resources to be used in its design and implementation. The systems architect's work should seek to avoid implementation issues and readily permit unanticipated extensions/modifications in future stages. Because of the extensive experience required for this, the systems architect is typically a very senior technologist with substantial, but general, knowledge of hardware, software, and similar (user) systems. Above all, the systems architect must be reasonably knowledgeable of the users' domain of experience. For example, the architect of an air traffic system needs to be more than superficially familiar with all of the tasks of an air traffic system, including those of all levels of users. The title of systems architect connotates higher-level design responsibilities than a software engineer or programmer, though day-to-day activities may overlap. Overview Systems architects interface with multiple stakeholders in an organization in order to understand the various levels of requirements, the domain, the viable technologies, and anticipated development process. Their work includes determining multiple design and implementation alternatives, assessing such alternatives based on all identified constraints (such as cost, schedule, space, power, safety, usability, reliability, maintainability, availability, and other "illities"), and selecting the most suitable options for further design. The output of such work sets the core properties of the system and those that are hardest to change later. In small systems the architecture is typically defined directly by the developers. However, in larger systems, a systems architect should be appointed to outline the overall system, and to interface between the users, sponsors, and other stakeholders on one side and the engineers on the other. Very large, highly complex systems may include multiple architects, in which case the architects work together to integrate their subsystems or aspects, and respond to a chief architect responsible for the entire system. In general, the role of the architect is to act as a mediator between the users and the engineers, reconciling the users' needs and requirements with what the engineers have determined to be doable within the given (engineering) constraints. In systems design, the architects (and engineers) are responsible for: Interfacing