What is Six Sigma Black Belt Certification? Six Sigma Black Belt Training and Certification will positively impact your career by providing a deep understanding of the leadership role within Six Sigma. A Six Sigma Online Black Belt Certification will demonstrate your ability to be a leader in the execution of Six Sigma projects. IASSC provides an unbiased independent third-party validation of Lean Six Sigma knowledge through our globally recognized Lean Six Sigma Black Belt, Green Belt and Yellow Belt Certifications. Arrange your IASSC Certification Exams now through our On-Demand Web-Based Testing System or in one of our testing centers anywhere in the world.