Use contextual inquiry to understand communication flows, sequence of tasks, the artifacts and tools people use to accomplish work, the impact and influence of the culture on the work, and also, the impact and influence of the physical environment on the work. A contextual interview is usually completed in a two-to three-hour session. How many people you need to interview depends on the scope of the project and work you want to support, but you need to interview multiple people in different user segments before the synthesis of contextual inquiry findings can begin (see Affinity Diagramming).