Understanding Six Sigma: Concepts, Applications and Challenges includes seven excellent chapters that have been prepared using state-of-the-art methodologies by professional researchers in this domain from seven different countries. The chapters in the book are titled as follows:"Sustainable Development of the Environment Using Six Sigma"; "DMAIC Six Sigma for Complex Processes Improvement"; "The Lean Six Sigma Methodology: Applications in Thoracic Surgery"; "The Link between Six Sigma and Business Performance"; "Integration of the Lean and Six Sigma Methodology to Improve Quality Performance in a Healthcare Organisation"; "Six Sigma: A Process Improvement Methodology"; and "Integrating Six Sigma into a Business Strategy: Workshop and Leadership".