The theory of constraints describes a workflow of how to work with constraints to increase the overall efficiency of a system. The theory was originally described by Elijahu M Goldratt in the book The Goal, and then further elaborated upon in the context of Technology and DevOps by Gene Kim in The Phoenix Project.

The workflow described is divided into five separate steps:

  • Identify
  • Exploit
  • Subordinate
  • Elevate
  • Repeat

By using the workflow below, the idea is to gain additional understanding about a system’s weaknesses and where time is best spent to further increase its efficiency. Ideas like Optimizations should be made at the bottleneck origin from this theory.

graph TD

 A[Identify]
 B[Exploit]
 C[Subordinate]
 D[Elevate]

 A --> B --> C --> D
 D --> |Repeat|A

Steps

Identify

  • What needs to be changed?
  • What should it be changed to?
  • What will cause the change?

Exploit

  • Create a buffer to avoid running out of work
  • Check quality before reaching the constraint
  • Ensure continuous operation
  • Move maintenance outside of production time
  • Offload, either internally or externally

Subordinate

  • Upstream
  • Downstream

Synchronize to the constraint capacity

Elevate

  • Performance Data
  • Top Losses
  • Reviews
  • Setup Reduction
  • Updates/Upgrades
  • Equipment

Repeat

  • Constraint has been broken: Find and eliminate the new constraint.
  • Constraint has not been broken: Run the process again with fresh eyes.