Defeating the enemy by any means has always been a goal of warring parties. This was also true during the First World War, when no stone was left unturned to eliminate the enemy, even by using aggressive chemicals or poisonous substances, which science readily provided. For this reason, it soon became necessary to provide one’s own soldiers with special equipment to protect them against this invisible enemy. In recent years the study of the gas\-defence equipment supplied to the warring armies has seen growing interest. This book, comprehensively illustrated with photographs of more than 200 original specimens preserved in private collections or museums, seeks to describe and illustrate the most important gas\-defence equipment used during the First World War by the imperial armies of Germany and Austria\-Hungary and by the army of the Kingdom of Italy.