This paper explores the fault-tree analysis approach to isolating failure modes within a system. Fault tree investigates potentially undesirable events and then looks for failures in sequence that would lead to their occurring. Relationships among these events are symbolized by AND or OR logic gates, AND used when single events must coexist to produce the more general event. Other fault-tree symbols represent input or output types or failure-oriented events, and are classified by their nature. The circle, for instance, points to a failure event in which further development is not required. In constructing the tree, decision-makers should develop each failure event so that cause and effect relationships can be identified, and thus recommendations leading to better communications or resource allocations made. (KS)