Why do you need a Scrum Master?

What's the point of a Scrum master when you can have a Project Manager?

There's no PM in Scrum — let's start there. The Scrum team has three core roles: the Product Owner (PO), the Scrum Master (SM) and the development team. You may also see a Tech Lead providing technical guidance to developers — that's a common variation of Scrum. Either way, Agile favours self-managed teams (see the 10 principles of agility).

Managers can be involved, and often are, but their responsibilities and level of influence differ from those of classic managers in most companies.

How might a manager be involved in Scrum?

A Product Owner and a Scrum Master together already hold enough authority to lead a team, and the team itself has meaningful self-management. But Scrum is not strictly bounded: if your organisation has a large pool of developers and too many processes to handle, and a manager would clearly help — hire one. Just be careful about which responsibilities and authority you delegate to that person.

"I prefer to think of the project manager as an assistant to the Scrum teams. In this role, the project manager is expected to have the whole-system perspective and to work diligently with each of the clusters or individual teams to ensure that everyone has the appropriate understanding of what cross-team coordination is required — but the teams still own the coordination." — Kenneth S. Rubin, Essential Scrum: a Practical Guide to the Most Popular Agile Process

What are the responsibilities of the Scrum Master?

The Scrum Master is the agile coach for both the development team and the Product Owner. They remove impediments the team faces during development and act as a servant leader and interference shield. As a servant leader, the Scrum Master doesn't think the team owes them the work done — they help the team get it done. Importantly, the Scrum Master has no hiring or firing authority and no command-and-control management power.

What should the Scrum Master know?

• the fundamental principles behind agile methodologies
• the differences between Agile and traditional project-management approaches
• the benefits of iterative and incremental delivery
• how to coordinate and facilitate Scrum meetings
• how to apply Agile and Scrum principles to real-world scenarios

Does every team need a Scrum Master?

No. One Scrum Master can comfortably support several teams. The right ratio depends on each team's size and experience with Scrum: an experienced Scrum team typically needs less attention than a team coming from a traditional waterfall approach.

Can a team work without a Scrum Master?

Yes, but then a manager has to perform the Scrum Master's functions and act in a "Scrum way" — coach and motivate rather than command and control.