Lean and six sigma strategies use a belt system very similar to many forms of martial arts to designate the experience, skill and contribution to the organizations strategy for each individual. As you may know already there are 5 different belts that a practitioner can obtain.
White Belt - A white belt is generally trained in basic elements of lean and six sigma. They typically are capable of understanding language and activities that are going on around them and often times work with problem-solving teams. Although White belts are not often designated full time to a continuous improvement team they often times are able to assist others who may have little to no exposure in lean or six sigma.
Yellow Belt - A yellow belt is often times a subject matter expert in specific areas of an organization. Generally yellow belts will participate in projects as an assigned team member and are often capable of providing direct assistance with process improvements and data collection.
Green Belt - Green belts are very skilled in terms of improvement projects and analysis. The green belt is often of the same skill set as a black belt but lacks the experience needed to coach, guide, mentor and direct other individuals.
Black Belt - A black belt has mastered almost all aspects of their niche. Black belts often lead in initiatives, problem solving and help support coaching, training and facilitation of other individuals.
Master Black Belt - A master black belt is often referred to as sensei or coach. Often master black belts are full time coaches establishing programs to advance the organizations skill set and supporting as an "internal" consultant on large scaled projects.