ASQ Master Black Belt Book

Updated on 23 September 2026. What’s new: exam time corrected to 5 hours and 20 minutes inside the five-and-a-half-hour appointment ASQ lists for the CMBB

Most ASQ certifications begin with an application and end with an exam. The Certified Master Black Belt (CMBB) begins with a judgement. Before you can book a seat, a panel of practising Master Black Belts reads a portfolio of your Black Belt work and scores it against three indicators. Fail there and the exam never happens. That review, not the 110-question paper, is where most CMBB attempts end.

This guide is written for Certified Six Sigma Black Belts who have run enough projects to wonder whether the next credential is within reach. It sets out who ASQ lets apply, what the portfolio has to prove and how it is scored, what the whole thing costs, when the exam is actually held, how the scored questions are distributed across the Body of Knowledge, and what keeps the credential alive afterwards. Every figure below is either from the exam details we publish or from ASQ's own pages, checked in September 2026.

One structural point is worth fixing in your head before anything else, because it changes how you budget and how you plan your year. The CMBB is two gates with two separate payments. The first buys a reading of your career evidence. The second buys a seat in a Prometric test centre. Passing the first tells you nothing about the second, and paying for the first does not reserve the second.