Insanely Short Iterations

XP recommends short iterations, so the XP Game uses really short iterations: 180 seconds. These 180 seconds include only the "pure" implementation time, without counting any preparations or the time to perform acceptance tests.

These 180 seconds are the "budget" the players can allocate when making their release plan: The total estimated time of all the chosen stories must not exceed 180 seconds.

If all the chosen stories have been implemented and there's time left, the customer may choose some more stories. The iteration ends after exactly 180 seconds, not a second more, not a second less. If the team is still working on a story, this story is abandoned. This emphasizes the fixed iteration time, during which the customer can change only scope and priority.

When the iteration is about halfway through, the team compares their actual implementation to their plan: Are we ahead, behind, or right on schedule? Should we warn the customer that they might have to reduce scope?

We used to measure time with a stopwatch, but an hourglass is more fun, more tactile, and more visible. We don't care about one-second precision; we need to know if we're halfway or almost done. It turns out that even with such simple tracking tools as a list of story cards and an hourglass, we can give the customer pretty accurate and useful feedback on our progress. The sight of the last grains of sand sliding down the hourglass reminds the players that time is finite and increases the pressure to finish the implementation of their story.