XP Roles and Tasks

XP defines a more limited set of roles and tasks than Unified Process. The XP roles usually have much broader scope than Unified Process roles. There is a definite push in XP to move away from specialization where only one person on a team has knowledge of specific and critical parts of the system or technology. The consequence is that the XP roles usually map to more than one Unified Process role. Some Unified Process roles/tasks/artifacts do not map to anything in XP as XP has a somewhat smaller scope than Unified Process.

Definition of Roles and Tasks in Unified Process

Roles are typically realized by an individual or a set of individuals working together as a team. A project team member typically fulfills many different roles. Roles are not individuals; instead, they describe how individuals behave in the business and what responsibilities these individuals have. While most roles are realized by people within the organization, people outside of the development organization play an important role. A role is an abstract definition of a set of tasks performed and artifacts generated.

Roles have a set of cohesive tasks to be performed. These tasks are closely related and functionally coupled and are often best performed by the same individual. Tasks are closely related to artifacts. Artifacts provide the input and output for the tasks and the mechanism by which information is communicated between tasks.