A Timebox sets a fixed maximum duration for an activity. When time runs out, work stops regardless of whether everything is finished. The underlying principle: time is fixed, scope is variable. This reversal of the usual logic enforces focus and prioritization, because the team is forced to start with what matters most.
In Scrum, all events are timeboxed. The Daily lasts a maximum of 15 minutes, Sprint Planning for a two-week Sprint a maximum of four hours, the Retrospective a maximum of 90 minutes. The Sprint itself is also a Timebox. Outside of Scrum, the principle appears in the Design Sprint, where teams move from problem definition through prototype to user test in five days. The Timebox prevents perfectionism and endless discussions by setting a clear endpoint.
The concept has historical roots in the Pomodoro Technique by Francesco Cirillo from the 1980s. In Scrum, timeboxing is not an optional tool but a structural element that determines the rhythm of the entire framework.