In Agile frameworks, particularly Scrum, the concept of a timebox refers to a fixed period during which specific work is completed and made ready for review. The optimum length of a timebox (or Sprint) is typically two to four weeks. This duration strikes a balance between allowing enough time to complete meaningful work and maintaining a high frequency of feedback and adaptation. Shorter timeboxes (such as one week) might not provide sufficient time to produce a potentially shippable product increment, while longer timeboxes (over four weeks) might delay feedback and the ability to respond to changes. The two to four-week duration supports the Agile principle of regular delivery of valuable software and facilitates a continuous improvement process through frequent retrospectives and planning sessions. References:Business Analysis document, sections on Agile practices and Sprint planning.