The Scrum Team consists of a Product Owner, the Development Team, and a Scrum Master. Scrum Teams are self-organizing and cross-functional. Self-organizing teams choose how best to accomplish their work, rather than being directed by others outside the team. Cross-functional teams have all competencies needed to ;accomplish the work without depending on others not part of the team. The team model in Scrum is designed to optimize flexibility, creativity, and productivity. The Scrum Team has proven itself to be increasingly effective for all the earlier stated uses, and any complex work.

Scrum Teams deliver products iteratively and incrementally, maximizing opportunities for feedback. Incremental deliveries of “Done” product ensure a potentially useful version of working product is always available.

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 be useful. The Product Owner and Scrum Master roles are not included in this count unless they are also executing the work of the Sprint Backlog.

Multiple Scrum Teams often work together on the same product. One
Product Backlog is used to describe the upcoming work on the product. A
Product Backlog attribute that groups items may then be employed.

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If there are multiple Scrum Teams working on the system or product release, the Development Teams on all the Scrum Teams must mutually define the definition of “Done”.

The Development Team consists of professionals who do the work of delivering a potentially releasable Increment of “Done” product at the end of each Sprint. A “Done” increment is required at the Sprint Review. Only members of the Development Team create the Increment.

Development Teams are structured and empowered by the organization to organize and manage their own work. The resulting synergy optimizes the Development Team’s overall efficiency and effectiveness.

Development Teams have the following characteristics:

They are self-organizing. No one (not even the Scrum Master) tells the Development Team how to turn Product Backlog into Increments of potentially releasable functionality;

Development Teams are cross-functional, with all the skills as a team necessary to create a product Increment;

Scrum recognizes no titles for Development Team members, regardless of the work being performed by the person;

Scrum recognizes no sub-teams in the Development Team, regardless of domains that need to be addressed like testing, architecture, operations, or business analysis; and,

Individual Development Team members may have specialized skills and areas of focus, but accountability belongs to the Development Team as a whole.

The Product Owner is responsible for maximizing the value of the product resulting from work of the Development Team. How this is done may vary widely across organizations, Scrum Teams, and individuals.

The Product Owner is the sole person responsible for managing the Product Backlog. Product Backlog management includes:

Clearly expressing Product Backlog items;

Ordering the items in the Product Backlog to best achieve goals and missions;

Optimizing the value of the work the Development Team performs;

Ensuring that the Product Backlog is visible, transparent, and clear to all, and shows what the Scrum Team will work on next; and,

Ensuring the Development Team understands items in the Product Backlog to the level needed.

The Product Owner may do the above work, or have the Development Team do it. However, the Product Owner remains accountable.

The Product Owner is one person, not a committee. The Product Owner may represent the desires of a committee in the Product Backlog, but those wanting to change a Product Backlog item’s priority must address the Product Owner.

For the Product Owner to succeed, the entire organization must respect his or her decisions. The Product Owner’s decisions are visible in the content and ordering of the Product Backlog. No one can force the Development Team to work from a different set of requirements.

The Scrum Master is responsible for promoting and supporting Scrum as defined in the Scrum Guide. Scrum Masters do this by helping everyone understand Scrum theory, practices, rules, and values.

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.

The Scrum Master serves the Development Team in several ways, including:

Coaching the Development Team in self-organization and cross-functionality;

Helping the Development Team to create high-value products;

Removing impediments to the Development Team’s progress;

Facilitating Scrum events as requested or needed; and,

Coaching the Development Team in organizational environments in which Scrum is not yet fully adopted and understood.

The Scrum Master serves the Product Owner in several ways, including:

Ensuring that goals, scope, and product domain are understood by everyone on the Scrum Team as well as possible;

Finding techniques for effective Product Backlog management;

Helping the Scrum Team understand the need for clear and concise Product Backlog items;

Understanding product planning in an empirical environment;

Ensuring the Product Owner knows how to arrange the Product Backlog to maximize value;

Understanding and practicing agility; and,

Facilitating Scrum events as requested or needed.