The design and implementation of fail-safe mechanisms to prevent a process from producing Defects. This activity is also know by the Japanese term poka-yoke, from poka (inadvertent errors) and yokeru (to avoid) - pronounced POH-kuh YOH-kay. Although this common-sense concept has been around for a long time, it was more fully developed and popularized by Shigeo Shingo in Japan.
The emphasis here is on error prevention rather than resolution, where efforts are made to reduce or eliminate the opportunities for committing Errors. The frequency and the attendant cost of Errors is a function of the number of opportunities to make Errors, so designing a product or process to reduce these opportunities will almost certainly reduce the number of Errors arising from performing a process or using a product. This is often done by reducing the number of steps in the process or the number of parts in the product.
MoreSteam.com's Toolbox - Error Proofing - http://www.moresteam.com/toolbox/error-proofing.cfm Poka-Yoke Resources from LeanCEO.comTraining Presentations, Tutorials, Examples - http://www.leanceo.com/topics/poka-yoke/ Error Proofing Overview - American Society for Quality (ASQ) - http://www.asq.org/learn-about-quality/process-analysis-tools/overview/mistake-proofing.html