Scrum Roles

Several roles are defined in Scrum; these are divided into two groups; pigs and chickens, based on a joke about a pig and a chicken.

A pig and a chicken are walking down a road. The chicken looks at the pig and says, "Hey, why don't we open a restaurant?" The pig looks back at the chicken and says, "Good idea, what do you want to call it?" The chicken thinks about it and says, "Why don't we call it 'Ham and Eggs'?" "I don't think so," says the pig, "I'd be committed, but you'd only be involved."

So the "pigs" are committed to building software regularly and frequently, while everyone else is a "chicken" - interested in the project but really indifferent because if it fails they're not the pigs - that is, they weren't the ones that committed to doing it. The needs, desires, ideas and influences of the chicken roles are taken into account, but are not in any way allowed to affect, distort or get in the way of the actual Scrum project.

"Pig" roles
The Pigs are the ones committed to the project in the Scrum process - they are the ones with "their bacon on the line."

• Product Owner - Represents the voice of the customer. He/she ensures that the Scrum Team works with the "right things" from a business perspective. The Product Owner writes user stories, prioritizes them and then places them in the product backlog.

• ScrumMaster - Scrum is facilitated by a ScrumMaster, whose primary job is to remove impediments to the ability of the team to deliver the sprint goal. The ScrumMaster is not the leader of the team (as the team is self-organizing) but acts as a buffer between the team and any distracting influences. The ScrumMaster ensures that the Scrum process is used as intended. The ScrumMaster is the enforcer of rules. A key part of the ScrumMaster's role is to protect the team and keep them focused on the tasks in hand.

• Team - Have the responsibility to deliver the product. A team is typically made up of 5–9 people with cross-functional skills who do the actual work (designer, developer, tester, technical communicator, etc.).

"Chicken" roles
Chicken roles are not part of the actual Scrum process, but must be taken into account. An important aspect of an Agile approach is the practice of involving users, internal business groups and stakeholders into portions of the process. It is important for these people to be engaged in the outcome of the project by providing feedback into the development, its review and planning for each sprint.

• Users - The software is being built for the someone. "If software is not used"—much like "the tree falling in a forest" riddle—"was it ever written?"

• Stakeholders (customers, vendors) - These are the people who enable the project and for whom the project will produce the agreed-upon benefit[s], which justify its production. They are only directly involved in the process during the sprint reviews.

• Managers - People who will set up the environment for the product development organizations.