Lt Col C. N. M. Blair is chiefly remembered for authoring Guerilla Warfare (1957), a restricted Ministry of Defence publication that remains one of the most authoritative official studies of Britain's experience in irregular warfare during the Second World War. Drawing upon classified government and military records, Blair's work combines historical analysis with a systematic assessment of lessons learned from British-sponsored guerrilla campaigns across occupied Europe and beyond. Designed as both a historical survey and a practical doctrine manual, it examined how the United Kingdom might cultivate, support, and direct resistance movements operating behind enemy lines. The publication is notable not only for its scope and official provenance but also for its rarity. With only 1,000 copies originally printed, Guerilla Warfare remains a scarce and highly sought-after source for historians of special operations, resistance movements, and unconventional warfare.