The Inquiry Cycle is a formal structure for describing and supporting
discussions about system requirements. It divides requirements analysis into
three intertwined processes: proposing or writing requirements, challenging or
discussing them, and refining or improving them. In this paper, we present
an extended example (a meeting scheduler) of the Inquiry Cycle in operation,
categorize the types of requirements discussion that occur in practice, and
suggest some heuristics for analyzing requirements. We also explain how
concrete scenarios improve analysis.