Development Team Size
Optimal Development Team size is small enough to remain nimble and large enough to
complete significant work within a Sprint. Fewer than three Development Team members
decrease interaction and results in smaller productivity gains. Smaller Development Teams may
encounter skill constraints during the Sprint, causing the Development Team to be unable to
deliver a potentially releasable Increment. Having more than nine members requires too much
coordination. Large Development Teams generate too much complexity for an empirical process
to manage. The Product Owner and Scrum Master roles are not included in this count unless
they are also executing the work of the Sprint Backlog.
The Scrum Master
The Scrum Master is responsible for ensuring Scrum is understood and enacted. Scrum Masters
do this by ensuring that the Scrum Team adheres to Scrum theory, practices, and rules.
The Scrum Master is a servant-leader for the Scrum Team. The Scrum Master helps those
outside the Scrum Team understand which of their interactions with the Scrum Team are helpful
and which aren’t. The Scrum Master helps everyone change these interactions to maximize the
value created by the Scrum Team.