How a worker or workers serve as a central point for coordinating the activities of a group, collecting, distributing and disseminating (selecting, buffering, filtering, directing) information
We wish to highlight three roles in the XP process that serve as points of coordination:
1. The Team Leader: The team leader will often be the first point of contact for some information that needs to go elsewhere, both within the organisation and with outside clients. They will be told things and then pass that information on to others.
2. The Tracker: The tracker - who is responsible for "keeping track of the rate at which the team works" - serves as the point of coordination for group tasks. What is interesting is that their role is achieved primarily through the use of the cards (task, story, defect, see ArtefactAsAnAuditTrail). The tracker "copies numbers and (e.g. completion) dates from the stacks of cards (or cards on the noticeboard) into a spreadsheet that appears each week on the noticeboard as a summary of project progress" The way the cards work their way round the office follows the work progress and when they are placed on the tracker's desk the task is completed. These features of work mean that the tracker provides an account of work progress through representing details of them on specific artefacts and furthermore, the completion of tasks is visible as people placing them on the tracker's desk.
3. The Customer: Commonly an individual is nominated from the customer organisation to perform the reciprocal job as the 'Team Leader' but from across the other side of the organisational boundary (i.e. the customer perspective). They may be the point of contact and field requirments from different areas of the business and speak 'with a single voice' to the developers.
In this case the types of activity carried out by the Team Leader, The Tracker and The Customer are fairly familiar across many different development processes. Most have designated developer and customer personnel whose job it is to manage other workers, coordinate with outside organisation and to track the project. We would like to draw comparison only by suggesting that the greater group cohesion promoted by XP may make the job of the team leader easier as coordination is fostered in the work itself. Furthermore, it is worth pointing out that the cards themselves and their movement through the office facilitate tracking with an ease that may not be as ready with other methods.
ReceptionistAsHub (wiki version)
http://www.comp.lancs.ac.uk/computing/research/cseg/projects/pointer/patterns/receptionistAsAHub/receptionistAsAHub.html (Legacy site)