The role of the structural designer is to design a building or structure that is safe, reliable, functional and economical to build and maintain.

Building codes set out design loads and contain rules governing the ways in which these are to be applied, often by way of reference to design standards. In earlier times, structures were built using intuition, trial and error, and the rules of proportion acquired through experience. This led eventually to (increasingly sophisticated) design by calculations based on assessment of successful buildings, experimental work and mathematical modelling of the behaviour of materials and structural systems.