Click for a larger image

The viable system model (VSM) is a model that supports organizations to get in control of their performance, in a changing environment. The VSM describes the structure of an autonomous system that is capable of adjusting itself (and its performance) to changing requirements. A viable system can survive in a context that is continuously changing.

The VSM is based on regulation theory (cybernetics), so that it supports control. It is not meant to stimulate creativity. If you are looking for a mechanism that helps you deliver services in a dependency relationship where continuity is core, then the VSM is a very useful model. The model, however, is rather theoretic, and for many it is hard to get a grip on its meaning and on the way it works. If you do understand the VSM but you are still stuck with the question "but how?", you will find an ideal partner for VSM in USM.

USM's setup is highly analogous with the VSM: it provides a control mechanism, but now based on a management architecture, specifying a management system. This means USM focuses at the lower regions of the VSM. USM is set up in very simple structures with very practical components, making it easy to support the approach of the VSM in practice.

Check this video if you want to see how USM supports the VSM and how USM also works with Ashby's Law of Requisite Variety.