The history of the Special Operations Executive during World War II has been the subject of many books down the years. This is a detailed account of the development of equipment and techniques upon which the success of its subversive activities relied. SOE's behind-the-scenes research and development programme ranged from high explosive technology to chemical and biochemical devices; from the techniques of air supply to incendiarism; from camouflage to underwater warfare; and from radio communciations to weaponry. This is a well-documented account of how scientific and technical skills were exploited in support of the heroic efforts of SEO agents world wide during World War II.