Lean Manufacturing and Six Sigma Definitions

Glossary terms, history, people and definitions about Lean and Six Sigma

Time-motion study

Time and motion is a business efficiency technique combining the time study work of Frederick Taylor, with the motion study work of Frank and Lillian Gilbreth.

The systems of time and motion studies are frequently assumed to be interchangeable terms, descriptive of equivalent theories. However, the underlying principles and the rationale for the establishment of each respective method are dissimilar, despite originating within the same school of thought.


Time study is a direct and continuous observation of a task, using a timekeeping device (e.g., decimal minute stopwatch, computer-assisted electronic stopwatch, and videotape camera) to record the time taken to accomplish a task.

It is often used when:

  • there are repetitive work cycles of short to long duration,
  • wide variety of dissimilar work is performed, or
  • process control elements constitute a part of the cycle.

Motion study is in contrast to, but motivated by Taylor’s time study methods. The Gilbreths made use of scientific insights to develop a study method based upon the analysis of “work motions,” which involved filming the details of a worker’s activities and their body posture while recording the time.



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Time and motion study, Time-and-motion study