Because all construction takes place in or on the ground, geotechnical engineering plays a crucial role in all civil engineering projects. The need to investigate the ground is of vital importance before any construction work takes place. The failure to carry out adequate site investigations often has had dramatic and expensive consequences on construction projects

Geotechnical engineers require a wide variety of skills and, in general, need to be smarter than other kinds of engineer. Whereas most engineers have the luxury of specifying the materials they use, the geotechnical engineer has no choice but to work with the natural soil and rock as he or she finds it. These natural materials often have extremely variable properties that may change over time, perhaps due to changes in groundwater pressure, or, in the case of fill materials, due to biodegradation. Developing predictive models of ground behaviour is an extremely difficult, but key area, for the geotechnical engineer.

To become a competent geotechnical engineer requires a degree, postgraduate training and many years of practical experience. However, even the most highly trained and experienced geotechnical specialists depend on many other skilled professionals to implement their projects. These include geophysicists and surveyors, civil and structural engineering contractors, tunnelling and mining engineers, drilling, piling and foundations contractors, geologists, hydrogeologists, dewatering and ground improvement contractors, geochemists and analytical service companies.

Contracting companies are, in turn, dependent on technology developed by manufacturers of the specialized instruments, plant and equipment involved in ground engineering. Technical advances made by manufacturers continue to have a massive impact on the way in which projects are designed and carried out in the field.