ABSTRACT
There can be no doubt that we should aim to design safe structures, but just what we mean by safety and how we attempt to ensure it is not so straightforward. Safety is one of those concepts that is difficult to define. Dictionaries give many shades of meaning but, for the purposes of structural design, we require a precise, mathematically acceptable definition. We shall work towards such a definition by discussing the problems relating to safety and how the treatment of safety has developed over the years.
