toc - the theory of constraints

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TOC stands for “Theory of Constraints”, a theory that grew into a system-based management approach that provides the means to optimise organisational performance.

The power of TOC comes from
  • Appreciation of systems: knowledge that the whole system can be significantly more valuable than the sum of its parts
  • Understanding the nature of uncertainty and managing it effectively
  • Understanding systemic cause and effect relationships to focus management attention
  • Recognising real leverage points in value creation, whether they are physical or behavioural
Ensemble uses the Thinking Process (TP) to develop strategy.

In order to make this strategy into reality, Ensemble uses the following techniques:
  • An operations approach called Drum-Buffer-Rope (DBR)
  • A distribution and supply chain method called Replenishment
  • A project planning and execution management approach, called Critical Chain (CC)
TOC has a unique way of measuring an organisation’s progress. This is known as Constraint Accounting (CA), and it underpins the Thinking Process, Drum-Buffer-Rope, Replenishment and Critical Chain operational solutions.

The underlying process used in all aspects of TOC is the Five Focusing Steps which can be applied to all areas of the business.




This method helps us to focus our efforts to maximise system improvement.

It begins with the assumption that any system has something holding it back, preventing it from achieving more of its goal – a constraint. The first step is therefore to identify this constraint.

Step 1 - Identify the constraint.
If a constraint governs the output of a system, then before the system output can be improved, there must be a clear idea of where that constraint is!

Step 2 - Exploit the constraint.
If a system is only capable of producing at the rate of its constraint (a chain is only as strong as its weakest link), then that part of the system must be kept busy all of the time and squeezed for all it is worth! One unit lost at the constraint is a unit lost for the system as a whole.

Step 3 - Subordinate to the constraint.
If there is a weakest link in a chain, then it follows that the rest of the chain has the ability to produce more than the weakest link. The role of the rest of the chain is not to produce more than the weakest link. Instead, it should help support it or be subordinate to its needs, ensuring the constraint is able to focus on doing only what it is meant to.

Step 4 - Elevate the constraint.
Eventually the system will reach a point where its constraint has been exploited or squeezed to its maximum. At this point, investment in additional capacity is usually considered, and this is known as “elevation” of the constraint. The elevation step is usually, but not always, a strategic decision.

Step 5 - Do not let Inertia become the constraint.
Once the system constraint has been elevated, the constraint will move to a new point in the system! The system therefore cannot be managed the same way as before and Step 1 must be revisited. In this way, a process of continuous improvement begins.