This handbook is a helpful guide to Six Sigma process improvement and variation reduction. Individuals studying to pass the ASQ Certified Six Sigma Yellow Belt (CSSYB) exam will find this comprehensive text invaluable for preparation, and it is also a handy reference for those already working in the field. The handbook offers a comprehensive understanding of the Body of Knowledge (BoK), which will allow readers to support real Six Sigma projects in their current or future roles. This handbook, updated to reflect the 2022 BoK, includes: - A detailed explanation of each section of the CSSYB BoK - Essay-type questions in each chapter to test reading comprehension - Numerous appendices, a comprehensive list of abbreviations, and a glossary of useful terms - Online contents, including practice exam questions - Source lists, which include webinars, tools and templates, and helpful publications