Very little is known of the real life Lin Kuei clan of martial artists, but their philosophies and techniques have long served as inspiration to those pursing a fundamental knowledge of martial arts, as well as to the popular representation of ninjas throughout media. Li Hsing, a modern influence amongst the Lin Kuei, trained under one of the clans patriarchs, Shr-Lin, and authored this treatise with numerous photographs and explanations to keep the Lin Kuei practice alive.