Steps in The Theory of Constraints
TOC includes five focusing steps designed to concentrate improvement efforts on the constraint most likely to have a positive impact on a system.
The five focusing Steps in The Theory of Constraints
1- Identify the system constraint
The organization should identify what part of the system constitutes the weakest link (the
constraint), and determines whether it is a physical constraint or a policy constraint.
Policy constraint usually more difficult to identify and eliminate but removing them
normally results in a larger degree of system improvement than the elimination of physical
constraint. An organization must have some means of combating the process by which people
become prisoners of their procedures. The rule book becomes fatter as the ideas become
fewer. Almost every well established organization is a coral reef (intensity) of procedures
that were laid down (sacrificed) to achieve some long forgotten objectives.
By analyzing the current system, a system constraint could be identified where one step in
the process is taking too long to complete or is idle too long.
2- Decide how to exploit the constraint
Exploit the constraint means that the organization should wring (squeeze) every bit of
capability out of the constraining component as it currently exist without committing to
potentially expensive changes and/or upgrades.
Example : Scheduling of key machine time is changed and employees are redeployed from
non-constraint component to the constraint component.
3- Subordinate everything else
With a plan in place for exploiting the constraint, an organization adjusts the rest of the
system to enable the constraint to operate at maximum effectiveness and then evaluates the
results to see if the constraint is still holding back system performance. If it is, the
organization proceeds to Step 4. If it is not, the constraint has been eliminated and the
organization skips ahead to Step 5.
Example: Further analysis looks at actions to maximize flow through the constraint. With a
focus on throughput, the review team suggests ways to speed up the process such as reduced
setup times and use of the drum–buffer–rope system. Non-value-added activities are
eliminated. The idea is to keep the constraint busy without accumulating inventory or
accumulating work in the process.
4- Elevate the constraint
If an organization reaches Step 4; it means that Steps 2 and 3 were not sufficient in
eliminating the constraint. At this point, the organization elevates the constraint by taking
whatever action is needed to eliminate it; this may involve major changes to the existing
system, such as reorganization, divestiture, or capital improvements. Because these
typically require a substantial up-front investment, the organization should be certain that the
constraint can’t be broken in steps 2 and 3 before proceeding.
Elevating the constraint means that we take whatever action is required to eliminate the
constraint. When this step is completed the constraint is broken.
Example: Management considers how to increase capacity of the system (should steps 2 and 3
prove unsatisfactory in alleviating the constraint). Additional labor or more/new equipment
may be necessary.
5- Go back to step I, but beware of inertia
After a constraint is broken, the organization repeats the steps all over again, looking for the
next thing constraining system performance. At the same time, it monitors how changes
related to subsequent constraints may impact the constraints that are already broken, thus
preventing solution inertia.
Example: The organization considers a strategic response to the constraint. The goal is to
improve throughput. The product or the process may be redesigned or hard-to-manufacture
products may be eliminated, and so on.
Theory of constraints reports
TOC focuses on eliminating constraints and decreasing cycle time or delivery time. Performance measures used in implementing TOC will also identify critical success factors. Organizations often prepare a TOC report to highlight selected operating data and the throughput margin. TOC reports are valuable in identifying both profitability and critical success factors.