The twentieth century ushered in new forms of warfare. On the high seas the submarine would challenge the supremacy of surface craft, and in the air the aeroplane offered new forms of both attack and reconnaissance. The advent of the tank made cavalry redundant and speeded-up the pace of war. Concealment, or the ability to confuse the enemy, could profoundly affect military operations and individual survival. Uniforms became drab for concealment, but in their camouflaged forms could denote elite fighting units. Artists were mobilised to devise concealment and the natural world played its part. Assumptions were made that had to be corrected. This book explains the fascinating challenges of the new ways of warfare and how concealment by camouflage played its part.