The selection of the type of drilling or production platform appropriate to a particular off shore site depends, chiefly, upon the likely severity of the marine environment, the nature of the seabed, and the geotechnical properties of the underlying soils and whether there exists a requirement for on-site oil storage. Although these physical factors have all played important roles in shaping the evolution of offshore structures, particularly in the North Sea, economic considerations and the national preferences of client companies have on occasion been decisive.This paper traces the evolution of offshore oil production structures for the North Sea with particular emphasis on the role played by geotechnical engineering during the conception, design, and construction of some of the largest movable structures in the world.