SSM approach: Systemic – whole is greater than the parts. Iterative – steps repeated, not purely sequential. User-centred – focuses on stakeholders. Information-centred – focuses on gathering information. Qualitative – based on debate, negotiation and consensus. Problem exploration – focus on exploring ¬†understanding problem rather than solving it. Conceptual – modelling is conceptual, important to recognise if solutions identified involve […]


Six stage process developed by Checkland to create Root Definition. C – Clients/customers of system identified i.e. stakeholders. A – Actors involved in situation – key stakeholders. T – Transformation involved i.e. what are inputs, what is transformation and what are outputs. W – Weltanschauung/worldview – set of beliefs brought to the situation. O – Owners of system. E – […]

Soft Systems Methodology (SSM) stages 5 – 7

Stage 5 – Conceptual Models compared to problem expression and Root Definitions. Stages 2 – 5 reiterated if there are differences until Root Definition agrees with Conceptual Model. Differences likely between Root Definition and Conceptual Model due to more analysis being carried out in development of Conceptual Model. Stage 6 – Identify the feasible and desirable changes by comparing the […]

Soft Systems Methodology (SSM) stages 1 – 4

Methodology supporting Soft Systems analysis developed by Checkland. Seven stages: The Problem Situation The Problem Situation expressed Root Definitions of relevant systems Building Conceptual Models Comparison of the expressed Problem Situation and the Conceptual Models Feasible and desired changes Action to improve the situation Stages 1 & 2 – obtaining rich expression of problem situation, creation of rich pictures. Stage […]

Mess and Difficulty – Difficulty

Ackoff defines difficulty as: Situation is bounded – possible to identify system(s) involved. Problem(s) easily identified. Possible solutions can be identified. Timescales are limited or predictable. Limited/known number of stakeholders and groups involved. Both Hard and Soft systems have a cycle/iterative approach. Hard systems go into maintenance and back to requirements. Soft systems continually analyse problems. Different views on Hard […]

Mess and Difficulty – Mess

Ackoffs mess & difficulty useful for deciding to take hard or soft approach. Mess: Unbounded -difficult to identify boundaries, concept of boundary important in defining system. Problem(s) are unclear. No visible solutions – relates to not knowing what problem is. Many stakeholders and groups therefore many perspectives. Timescales long term.

Soft systems arrive

Concept – 1970s, driven by Peter Checkland. Checkland and Russell Ackoff acknowledged Hard Systems was mature but still problems where implemented and approach not always suitable. Ackoff (1974) – messes – often not possible to soleve – and difficulties – something solvable. Checkland – complexity, where involved, not always possible to identify. Involvement of humans – ‘soft’ issues – hard […]

The Wicked Problems

Situations containing complex systems – “wicked problem”, Horst Rittel in 1970s. – Easy problems have been solved, only difficult ones left as they cannot be defined let alone resolved. Ten significant characteristics (Webber and Rittel, 1973): No definitive formulation e.g. problem of poverty in Texas is very similar but subtly different from poverty in Nairobi – no practical characteristics describe […]

Design and Complexity

Four areas where design and complexity interact – Johnson (2006). Many designed systems are complex e.g. aeroplanes, cities, information systems, organisations. Designers need to understand complex dynamic processes used to fabricate & manufacture products & systems – design, product & processes c0-evolve. Social & economic context of design is complex. Involves market economics, regulations, trends, culture and fashion etc. Design […]

Soft Systems Introduction

Define and discuss Soft Systems approaches. Hard systems also known as mechanical systems – behaviours & boundaries can be successfully described in mechanical terms. Soft systems: fuzzy boundaries. Parts/elements difficult to identify. Hard systems thinking: maximise efficiency of system. Soft systems thinking: inclusive of different perspectives. Systems thinking assumes system has emergent properties & is therefore greater than the sum […]