When designing information systems as complex systems through Information Systems (IS) discipline, researchers and practitioners not only apply models, methods and theories of management and control – they also use the same from engineering, linguistics, cognitive science, environmental science, biology, social science, artificial intelligence, systems thinking and cybernetics and etc. This diversity of IS related disciplines derives from the nature of information systems as multi-faceted, multi-disciplinary entities with interacting dimensions and different design- and evolution concerns. We believe that for the design of large scale complex systems using IS discipline, like any other developing and evolving discipline, there should exist a theory, unified terminology, models and methodology. To model the discipline-as-a-system, we use Beer’s Viable System Model (VSM) and introduce three basic components of IS discipline as a viable discipline (system). A ‘co-evolution mechanisms’ for IS discipline is proposed, and a cybernetic model of co-evolution is applied to IS discipline.