Great ScrumMasters are rare. If you have one in your company, you have greater chance to be successful. Regrettably, the role of ScrumMaster is underestimated in most of the organizations, but without great ScrumMaster, your team will never "shine" or in other words be efficient, high-performing, self-organized, or proactive. Let's have a look at this role and see how great ScrumMaster works and how he/she helps the company to be more successful. It's not an easy job where for the ScrumMaster it is essential to learn several different concepts concerning team theory, system thinking, and coaching. The talk is based on concepts described in my new book The Great ScrumMaster - #ScrumMasterWay published by Addison-Wesley Professional as part of the Addison-Wesley Signature Series (Mike Cohn).