Through their day-to-day usage collaboration tools collect data on the work process. These data can be used to aid participants' retrospective reflection on the process. The paper shows how this can be done in software development project work. Through a case study we demonstrate how retrospective reflection was conducted by use of an industry approach to project retrospectives combined with the examination of historical data in Trac, an issue tracker. The data helped the team reconstruct the project trajectory by aiding the recall of significant events, leading to a shift in the team's perspective on the project. The success of the toolaided retrospective reflection is attributed to its organization as well as the type of historical data examined through the tool and the tool features for navigating the data. These insights can be used to help project teams determine the potential of their tools to aid retrospective reflection.
IntroductionSoftware development (SD) is highly cooperative work which has received considerable attention in CSCW [1][2][3] . In SD, mistakes are common as well as costly [ 4 ] , and learning from experience is essential [ 5 ] .In SD organizations using large integrated systems to support and coordinate work, efforts to have the organization learn from experience may be integrated into predefined work processes and supported by tool functionality for collecting and providing experience data. The idea of experience factories [ 6 ] reflects a similar idea. In other settings, as in agile software development [ 7 ] , learning from experience may be more informal and deferred to face-to-face project meetings and retrospective B. Krogstie ( ) and M. Divitini