Peter Oldham has a special interest in defence strategies and tactics of the First World War, ranging from the grand planning and organization of defence schemes to the parts played by the sapper who dug the trench and the tommy who has to man it. Having studied the evolution and changing theories of fixed and elastic systems, he then researched the part played by permanent fortifications and shell-proof protection for troops and services. His understanding of the problems of the supply and use of building and concreting materials is unrivalled. As a concrete technologist, he has spent twenty-five years testing and producing concrete materials and structures.