High quality kung fu can be defined by several factors: martial effectiveness, proper root & structure, underlying concepts & principles. While maintaining combat effectiveness with martial arts techniques (blocks, parries, strike, kicks, sweeps, traps, locks, etc.), it must also contain a fundamental practice of rooting in the stance and moving while maintaining this structure. At higher levels it should also contain principles and concepts related to the management of kinetic energy; how to sense, control, and disturb the structure or path of motion that the opponent creates.