Fifth, what techniques of data collection should be used in case research? Although interview
(either open-ended/unstructured or focused/structured) is by far the most popular data collection
technique for case research, interview data can be supplemented or corroborated with other
techniques such as direct observation (e.g., attending executive meetings, briefings, and planning
sessions), documentation (e.g., internal reports, presentations, and memoranda, as well as external
accounts such as newspaper reports), archival records (e.g., organisational charts, financial records,
etc.), and physical artefacts (e.g., devices, outputs, tools). Furthermore, the researcher should
triangulate or validate observed data by comparing responses between interviewees.