Socially and industrially globalized environment generates the need for flexibility of enterprises acting, cooperating and preserving their identity in various value and supply chains and socio-technical ecosystems. Achieving required flexibility, ability to cooperate, and ability to care for enterprise identity is possible via use of information systems that can provide a high level of variability of systemically organized information services. The points of variation may reside in types of information provided, in information, data, software, hardware, and network architectures, systems development methods, and in types of chosen information sources in enterprises and their environment. Vigorous models are needed to handle the variability in enterprises in general and in information systems in particular. St. Beer's Viable Systems Model known in organizational cybernetics is one of the candidates for handling and utilizing the variability to achieve enterprise viability via viable information systems.