Viable System Model

Stafford Beer, 1959–1985

Stafford Beer's model of the five functions any organisation needs to survive in a changing environment, repeating at every level from team to nation.

The Viable System Model (VSM) describes the structure that any system must have in order to be viable: able to maintain a separate existence in a changing environment. Stafford Beer developed it over several decades, most fully in Brain of the Firm (1972), The Heart of Enterprise (1979) and Diagnosing the System for Organisations (1985). Beer modelled it loosely on the human nervous system.

The five systems

  • System 1: Operations. The parts that do the primary work and deal directly with the environment, such as factories, teams or departments. Each is itself a viable system.
  • System 2: Coordination. Mechanisms that stop the operational units from interfering with each other, such as schedules, shared standards and protocols.
  • System 3: Control. Management of the operations as a whole in the here and now: allocating resources, setting targets, and the audit channel (System 3*) that checks what is actually happening.
  • System 4: Intelligence. Looking outward and ahead: the environment, the future, research and strategy.
  • System 5: Policy. Identity and values; balancing the present (System 3) against the future (System 4).

Key principles

Recursion. Every viable system contains viable systems and is contained in one. A team, a department, a company and an economy can each be analysed with the same model.

Variety. Following the Law of Requisite Variety, each channel between management and operations, and between the organisation and its environment, must be designed so that variety is balanced: enough autonomy below, enough information above.

Algedonic signals. Urgent alarm signals that bypass the normal hierarchy and go straight to the top when something threatens viability.

Use today

The VSM is used to diagnose organisations by asking which functions are missing or weak, and to design structures that give units maximum autonomy consistent with cohesion. It has been applied to firms, public services, cooperatives, and, in Project Cybersyn, a national economy.

Further reading

  • Stafford Beer, Brain of the Firm (1972; 2nd edn 1981)
  • Jon Walker, The Viable Systems Model: A Guide for Co-operatives and Federations (1991), free online
  • Patrick Hoverstadt, The Fractal Organization (2008)

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