Engineers and architects design buildings to stand, and the vast majority of them do so without major incident. Yet occasionally a building does collapse, bringing with it questions about the science, technology, and ethics of structures. Though they happen for a variety of reasons, collapses can be clustered into three groups: those resulting from natural disasters (earthquakes, mudslides, tornadoes, and the like); inadvertent collapses (because of flaws in design, use, and/or maintenance); and intentional destruction (including both planned demolition and malevolent attacks). Each type raises different, if related, ethical questions.

Two types of explanation exist for collapses. The first is focused on the mechanics or physics of the destruction; it asks what forces were acting on (and being produced by) what parts of the structure and in what fashion. The lessons drawn from such analyses will be, necessarily, structural or mechanical...