Waste comes in three main forms:

  1. Mura or waste due to variation

  2. Muri or waste due to overburdening or stressing the people, equipment or system.

  3. Muda also known as the “seven forms of waste”.

The following are the wastes most commonly associated with Lean.

  • Transportation: Is there unnecessary (non-value added) movement of parts, materials, or information between processes?

  • Waiting: Are people or parts, systems or facilities idle - waiting for a work cycle to be completed?

  • Overproduction: Are you producing sooner, faster or in greater quantities than the customer is demanding?






Muda comes in two flavors called Type-1 muda and Type-2 muda. What’s the difference? In both cases it fails to meet all three criteria for value-added as defined by your customer.

  • Type I muda — Non-value added, but necessary for the system to function. Minimize this until you can eliminate it.

  • Type II muda — Non-value added and unnecessary. Eliminate this first!