A Lean Six Sigma Black Belt is a professional trained in Lean Six Sigma methodology and leads complex improvement projects, typically on a full-time basis. A Lean Six Sigma Black Belt possesses a thorough understanding of all aspects of the Lean Six Sigma method, including a high level of proficiency in the subjects contained in the Define, Measure, Analyze, Improve and Control (DMAIC) phases. A Lean Six Sigma Black Belt understands how to implement, execute, interpret and apply Lean Six Sigma to an advanced level of proficiency.

A Lean Six Sigma Green Belt is a professional who is proficient in the core advanced elements of the Lean Six Sigma methodology and leads improvement projects or serves as a team member as part of more complex improvement projects led by a certified black belt. A Lean Six Sigma Green Belt possesses a thorough understanding of all aspects of the Lean Six Sigma method including subject matter expertise contained in the Define, Measure, Analyze, Improve and Control (DMAIC) steps.

A Lean Six Sigma Yellow Belt possesses in-depth knowledge of the elementary aspects of the Lean Six Sigma Methodology, including proficiency in the subjects contained in the Define, Measure and Control (DMC) phases as defined by the Lean Six Sigma Yellow Belt Body of Knowledge. A Lean Six Sigma Yellow Belt understands how to implement, execute, interpret and apply Lean Six Sigma in a skilled but limited and/or supportive context.