Dharma combat, called issatsu (一拶, いっさつ?, literally "challenge") or shosan in Japanese, is a term in some schools of Buddhism referring to an intense exchange between student and teacher, and sometimes between teachers, as an occasion for one or both to demonstrate his or her understanding of the Dharma and Buddhist tenets. It is used by both students and teachers to test and sharpen their understanding. Practice is primarily seen in Zen traditions, particularly Rinzai Zen and the Kwan Um School of Zen. In both, it is a key component in the Dharma transmission process.